A hundred did-you-knows seems like a nice round number. I've quoted my current set of notes below; suggestions for additions are most welcome. I'll update the list in this message as new ideas come in, and clean up some of my rough notes, and eventually copy everything into the LifeWiki.
Should related rules be mentioned occasionally, or should we stick with B3/S23 only for this collection?
Current collection on LifeWiki (for reference): did you know…
- that the largest interesting pattern constructed, the caterpillar, contains over 11 million cells?
- that the Gosper glider gun was the first pattern to be discovered that exhibits infinite growth?
- that the block-laying switch engine and the glider-producing switch engine are the only two infinitely-growing patterns that are known to have ever occurred naturally from a nonsymmetric random starting configuration?
- that oscillators are known that oscillate at all periods other than 19, 23, 34, 38 and 41?
- that the pentadecathlon and the blinker are the only known oscillators that are polyominos in more than one phase?
- that it is impossible for a period 3 oscillator to be a phoenix?
- that the methuselah with the longest known lifespan, 40514M, lasts for over 40,000 generations before stabilizing? The second-place holder, Fred, runs for over 35,000 ticks.
- that replicators with quadratic population growth are known to exist in Conway's Game of Life, but none have yet been found?
- that the first known period 37 and 51 oscillators were found in 2009?
- that a pattern whose population grows without bound but does not tend to infinity is known as a sawtooth?
- that there are over 6.5 million distinct strict still lifes with 24 or fewer cells?
- that infinitely-growing patterns can be constructed with as few as three gliders?
- that quadratically-growing patterns have been found with as few as 23 initial cells?
- that the blinker is the only known oscillator that is one cell thick?
- that the first spaceship found in Conway's Game of Life that travels in an oblique direction was discovered in 2010?
- that there are still lifes that can be split into four stable islands, but not two or three?
- that no new spaceships were discovered after 1970 until 1989?
- that eighteen spaceship velocities have been constructed, including two infinitely adjustable families of ships?
- that there are 71 distinct ways for two gliders to collide, but it is unknown how many distinct 3-glider collisions there are?
- that the first odd-period glider gun -- a period 565 p5-spark-assisted B-heptomino loop by [[David Buckingham]] -- was constructed in 1995?
- that even though the speed limit for spaceships is c/2 in a vacuum, in a medium of [[stripes agar]] there are “spaceships” that can travel at lightspeed along the stripes, or two thirds of lightspeed perpendicular to the stripes?
- that the smallest known spacefiller pattern consists of 187 cells? (need to fix Max / spacefiller2 articles on wiki)
- that there are now at least 36 known Herschel conduits, counting stable conduits only, and more than twice that number if oscillator-supported conduits are included?
- that as of January 2015, because diagonal Geminoids are still theoretical, [[half-bakery knightships]] are the only known spaceships with fixed slope but adjustable speed?
- that a pattern exists in which no cell in the unbounded Life plane ever becomes periodic?
- that several candidate universal constructors have been demonstrated in Conway’s Life, but as of the end of 2014 none have been formally proven to be universal?
- that there are dozens of known Cordership variants, including puffers, rakes and wickstretchers, with periods of any multiple of 96?
- that [[greyships]] have been constructed with speeds of c/2, c/3, c/4, c/5 and 2c/5?
- that most [[greyships]] travel parallel to the stripes in their included agars, but some [link?] travel perpendicular to the stripes, or “against the grain”?
- that a pattern has been constructed that calculates and prints out the digits of pi in decimal, and a similar one prints out the decimal digits of the Golden Ratio?
- that several different patterns have been constructed to display the sequence of prime numbers, and some have been adapted to display only prime pairs or Fermat primes?
- that two completely different types of knightships, the [[waterbear]] and the [[HBK]], were constructed in 2014?
- that no Caterpillar-type spaceships were completed for almost ten years after the original [[Caterpillar]] was constructed in 2004, but that two different designs, the [[waterbear]] and the [[centipede]], were finished in 2014?
- that the first spiral-growth pattern in Conway's Life was constructed in 2014?
- that among known glider recipes for irreducible objects, the [[Gemini spaceship]] has the largest known minimal recipe, currently 175,167 gliders -- the runner-up being the [[HBK]] with a 38,380-glider synthesis?
- ...
- [simsim314's suggestions]
- that in 2014 a new natural infinite growth pattern was discovered, starting from a symmetric random starting configuration?
- that the first self-constructing Conway's Life pattern was built in 2010?
- that the first stable reflector was found in October 1996, and the first fast stable reflector appeared in 2013, allowing the construction of oscillators of all periods >=43 ticks?
- that the first c/3 spaceship gun was constructed in 2014?
- that the first "macro-spaceship" gun (a Gemini spaceship gun) was constructed in 2010, followed by the HBK gun in January 2015?
- that the [[waterbear]] is the single known high-speed oblique spaceship?
- that there are no known lightspeed reflectors?
- that 24 ten-cell patterns exhibit infinite growth, with 17 unique pattern types, but that it has been proven that no nine-cell pattern exhibits infinite growth?
- that all still lifes up to 18 bits have a known glider synthesis, but it's still not known whether all still lifes are synthesizable.
Extrementhusiast: - ...that the French kiss remained without a glider synthesis until 2013?
- ...that the soup searches have reduced many glider syntheses?
- ... [half-finished thoughts, please help complete and extend!]
- that the smallest (period/size) self constructor is ...
- that the smallest known Conway's Life universal constructor consists of only X live cells?
- -- unitcell and metapixel patterns
- -- Look for other articles along the lines of quad-pseudo-still-life…
- -- Something about the soup search: power law (add actual power-law formula to Achim Flammenkamp’s LifeWiki page?)
EDIT: added a few more ideas -- - that it was shown in 2014 that any salvo of gliders, no matter how tightly packed, can be constructed by crashing together gliders whose initial positions are farther apart than any chosen finite distance?
- that no spaceships with velocities other than c/4 diagonal (glider), c/2 orthogonal (*WSS variants), and c/12 diagonal (Corderships) had known glider syntheses until 2003, when a 2c/5 spaceship gun was constructed?
- that after ten years with no new spaceship syntheses, a glider construction was found for the c/7 loafer in 2013?
- that constructions for X previously inconstructible spaceships were discovered in 2014?
- that there are N (127?) still lifes known to be constructible with four gliders, but it is not known if this is a complete list?