This is a place where I'll put down which games I think are definite must-buys, not-buys, and in-between. Think of this as a VB game buying guide based on rarity and quality.

Must-Buy Rare Titles (if you see these games, pick them up ASAP):
Jack Brothers -- Rare and good.
In Mouse's House -- Rare and foreign.
Virtual Fishing -- Rare and foreign.
Space Squash -- Rare and foreign.
V-Tetris -- Rare and foreign.

Titles to make a good, all-around solid VB game collection with:
Wario Land -- Decent side-scrolling adventure starring Wario.
Panic Bomber -- Classic, fun puzzle game.
Golf -- Great golf sim.
Tennis -- It probably came with your VB.
Mario Clash -- Old-school entertaining Mario pipe game.
Nester's Funky Bowling -- Bowling is really fun.
Vertical Force -- The best VB Shooter out there.

Pick up these titles if you're a collector:
Waterworld -- It sucks, but is very rare.
Any Japanese Language Game -- Foreign.

You'll like these games if you like the genre:
Tetris 3-D -- Tetris with a twist.
Virtual League Baseball -- The only VB baseball game.
Galactic Pinball -- It's pinball.
Red Alarm -- You like it, or you don't.
TeleRoboxer -- If you like PunchOut, you'll like this.