Picked up a few good items recently:
Thunder Force III (Genesis) - complete in box with manual for $28. Sure, the price was a bit steep, but TFIII is my all time favorite console shooter, and it's nice to finally have it in my collection.
Game Genie (Genesis) with code book for $7.
Sonic 3 for $3. Another game long missing from my collection. The cart label shows some wear, but at least I can now display Sonics 1-3 and Sonic & Knuckles on my shelf with TCP custom cases.
Air Buster (Genesis) for $4. So many good shooters for the Genesis. I missed this one back in the day, but it's a good pickup now. No case, but there's a nice scan here.
I passed on an original NES for $20 at Goodwill. It had everything except a power cord so I had no way to test it in the store. All sales final on electronics at Goodwill. I recently bought and had to return three different NES's at Game Exchange because none worked right, so looking back I'd be pretty upset if I dropped $20 (plus whatever it would cost for a new power cord) only to find out the NES was defective. I ended up buying a top loader for $65.