I'd try staffing agencies - they work with companies looking to hire new personnel.
In an economy like the current one, temporary positions are usually more than the permanent ones and are not as difficult to find.
If you have any programming experience, you might try that - good pay, most likely not physics related but still ...
If you want some physics-related research, you could see at your current school if they don;t have an opening or if they have some info on REU openings this summer, nationwide that is. I did just that after my senior year.
Also, you might wanna try getting in touch with someone from the school you will be moving to in the fall for grad work and see if they don;t have something - many schools have summer research positions for incoming students too.
that's pretty much from me.