Someone asked me this very question the other day.
"You can't spend it on anything like bills either," she stipulated.
"I guess I'd buy a new vacuum cleaner," was my response. I don't really need one, but I'd like to get a high-end one like one of the Miele HEPA vacuums or a Dyson the next time I buy one.
Now, I'm not the type that needs to have the best or the most expensive of anything, but the next vacuum I buy is going to be a sturdy one and I've found that with appliances you usually get what you pay for.
What would you do with an extra $1000?