My pickups for the weekend.

Aliens Infestation - DS - $8 new - I've heard good things about this one. Apparently it's like Metroid.
Barbie - NES $1 at a yard sale - I don't own it and I'm still undecided on going for a complete NES set and it came with a dust cover so I had to grab it

Project Horned Owl - PS1 (A good shooter), Thrasher Skate and Destroy - PS1 (loved this one back in the day) $4 each
Siren - PS2 - $4 - Slowly completing my PS2 survival horror want list
Chaos Field - GC - $5 - decent / one of the only SHMUPS for the GC
Tiny Toon Adventures: Buster's Hidden Treasure (complete) - $10 - but free with store credit that I got by trading in some DS stuff that was given to me
Wave Race 64 - $5 - free with credit
Yoshi's Story - $20 - free with credit - I've wanted this one for a while and glad I could finally find it at a decent price