My ds is 12 - He loves video games (pokemon for the wii,is his b-day request for next week), Harry Potter, Gift Certificate to Local Movies with Movie Cash, Maybe a Gamestop/EBGame GC he could find some Previous Used Games Pretty Cheap there, or you could if you know what he liked for xbox, ps2, gc, etc.
What about a cell phone? Ie trac phone you can pick up one for $20.00 with minutes?? My DS can not have one till he is 13.
My DD is 14 - Cell Phone minutes, manicure/pedicure,nail polish, mp3 player