Usually I get GAS for small, simple, random things, like a new pickup, a pick, sticker, anything like that.
Recently I was gassing for an acoustic, so I grabbed one for $22.
I have also has GAS for a new tele, simply because I hate the colour of my old one. I bought a red one as soon as I was able to.
I had major GAS for a Classic Vibe tele and Duo when they first came out.
I'm lucky I don't get bitten by the bug very often 😀