Top 5 of all time?! A hard question... just off the top of my head:

1/ K-Traxx - Hardventure (Technoboy mix)
2/ Brain Ovulation - Kicks & Bass (Acid Step mix)
3/ Warmduscher - Hardcore Will Never Die (Derb mix)
4/ Droid - Focus (Reverse Bass mix)
5/ Trance Generators - Wildstyle Generation (Klasic & Sanders mix)

I could think of 20 easily tho. :D

Hardstyle: