Well, I read through the whole $500 MTB Thread and Raiyn suggested someone make a thread like this, so I did

And if it's already been made before, I'll show myself the door

Some of my own suggestions (not recommendations, suggestions) in this price range

Specialized Hard Rock (XC, Sport etc.)
Giant Rincon
Gary Fisher Tarpon

Using the current cad-us exchange rate, a rockhopper would only be $500 canadian but alas, the cheap prices are not the same up here and the rockhopper costs $600 (canadian)

Thanks for reading!