Answers to the regex golf puzzles. These were actually pretty frustrating - inelegant solutions generally got better scores than elegant ones!

regex_golf

Regex Golf
http://regex.alf.nu/

My total score: 3569

Plain strings (205) - .*foo
Anchors (208) - k$
Ranges (202) - ^[a-f]+$
Backrefs (201) - (...).*\1
Abba (193) - ^(?!.*(.)(.)\2\1)
A man, a plan (172) - ^[^p]?(.)(.).?\2\1
Prime (285) - ^(?!(xx+?)\1+$)
Four (193) - ([aeiou])(.\1){3}
Order (198) - ^[^o].{4,5}$
Triples (569) - ([0136]0([023469]|1[25])|24|31|47|50|58|60|7[2568]|87)$|3.*05
Glob (384) - ^([bcdlrw][^ai]|p|[\*m](er|[fiptv]))
Balance (227) - ^$|^(<>)+$|^<{4}>(?!><{4})|^<<>(>(<|$)|<<<<>>)|^<<<(>><{1,3}>|>>><<|><|<<>>(<|>><|><>{0,2}<))
Powers (92) - ^(?!(x(xx)+?)\1*$)
Long count (220) - ^0.+0..1..1.. (..0)+..1.1 ..0..1..1.10.. ..11.{9}1
Long count v2 (220) - ^0.+0..1..1.. (..0)+..1.1 ..0..1..1.10.. ..11.{9}1