I get several and I leave them in the middle compartment in my car. And every so often when I'm feeling super cheap I'll check to see if I have a GC for whatever place I'm about to go into. I'm usually happy to find that I have $25 or even $50 (sometimes even 2 GCs to the same place totaling upwards of $100) to spend which either gets me all my shit for free or at least gives me a nice buffer at a place like Best Buy if I'm looking to buy a relatively expensive electronic device or something.
Then food GCs are always good to find.
Long story short I probably keep 80% of my gift cards for over 2 years mostly because I often forget to check for them. And it creates a nice surprise when I realize that OH SHIT I do have $100 to this place. Haha.