In reply to JackM92:
I think it is Chris Crack in the Meadow, Llanberis Pass, very short lived though, and mostly avoidable.
The Ysgo Crack, again the crack is mostly avoided though.
Made in Heaven at Porth Ysgo has a jam if I recall correctly.
Jelly Roll Roof at Porth Or although more just upsidedown weirdness off hand and foot jams.
Joe's Crack at the cromlech
Boysen's Roof is not really a crack though.
There are not that many that are sustained though. I would have thought it better to do some of the classic crack routes.
Dinorwig Unconquerable (E3 5c)
Grond (E2 5b)
The Mau Mau (E4 6a)
Comes the Dervish (E3 5c)
Foil (E3 6a)
Ferdinand (E2 5b)
Cream (E4 6a)
Void (E4 6a)