I managed to get a few games I would not have bought otherwise, totalling $10. All were UMD in generic cases with no manual.
For the deal:
SSX on Tour (I already had the Gamecube version)
Half-Minute Hero (I failed at the demos, but wanted it anyway)
Bought separately:
Brooktown High (less than $2)
At another Gamestop I found Half-Minute Hero with original case and manual. I bought it and will return the first back at the original store. That will mean the sale won't apply but after trying SSX on Tour, I'm ok paying the nonsale price for it, bringing the grand total to $12.50 or so for all three.
[Edit] And that's what happened, only getting back half the purchase price due to the sale. I'm ok with that.