There's too many to single one al time fav out, but here's a few all time classics imo:

CJ Bolland - Spring Yard
Jeff Mills - Step to Enchantment
The Advent - Bad Boy
Joey Beltram - Mentasm/Energy Flash
Damon Wild - Afghan Acid
Plastikman - Do da do Remix
Surgeon - Magneze

a few current favs:
Heroes x series
British Murder Boys
Some Henrik b stuff
Chris McCormack, various trax