The guy who recited 20k numbers of pi by memory alone used a system where he converted numbers into consonants and then grouped words or sentences together to remember a huge amount of numbers.
Here's how it works:
1: t, th, d (single downstroke) Ex: Take, THe, Dog 2: n (two downstrokes) Ex: Nose 3: m (three downstrokes) Ex: Money 4: r (the last letter of “four” is “r”) Ex: Road 5: L (you have five fingers on your Left hand) Ex: Life, driLL 6: j, soft g, ch, sh (“J” is a near mirror-image of “6”) Ex: Jelly, CHips, garaGe, SHoe 7: k, hard g, c, or x (“7” side-by-side with a mirror image form a sideways “K”) Kite, Goat, Cat, eXcel 8: f, v, ph (“8” is similar to the lower-case cursive “f”) Ex: Flame, eFFect, Vest, graPH 9: p, b (9 is a mirror-image of “P”) Ex: Pen, Ball 0: z, s, soft c or x (0 signifies “zero”) Ex: Zipper, Scarf, eXample, iCe
Vowels don't count, double consonants only count once, and you go by the pronunciation rather than the spelling. H, q, and w don't count, and x is listed here but it can get confusing with words like excellent, so it's best to use unambiguous words. I hope I explained it well enough!
I like phi better than pi, so for this I'll be using phi. You can use whatever numbers you want, but phi is the most irrational number and we can do this forever or until we're bored.
Anyway, the goal is to come up with sentences that make as much sense as possible, so it becomes easier to remember them.
Here's what I have so far:
They shot off some map of a fake rope fiber. If ravens are alive, show off my room, Jill. She may fight to cook. Nice mice bit a cop; face leakage. An efficient mall; rare fashion. Nick's lunch is rich; no vat of poison. Rare picks... coon skins are tough. Be my petite maker for a gal or save face. Cool move, chief bought kale in a teenage sham. My fashion—an animal. My shop might keep my tough sausage, so I cash a check. Nacho meal. They = 1 shot = 61 off = 8
...and so on. You can see some of these don't make much sense. Have fun!
Here's a place to get all the numbers you'll ever need: http://www.goldennumber.net/phi-million-places/