Inactivity

So I work at this company this summer. It's a big company, seemingly with lots of stuff to do.
I'm hired as a summer temp in the technical department, filling in for people on vacation and generally helping out. I'm working with a guy who I know (who also got me the job), and I pretty much just tag along, and help him with the technical stuff, since he has the administrative mind map of the company in his head (I've been here for little over a week, I do not).
On a normal day, we do very little work. Granted, it's summer, and the pace slows down, but this is ridiculous.
Now, he's gone on a two week vacation, and left me with virtually nothing to do. I ask my boss and the people around if anybody needs my help with anything, at this point it's anything at all really. Moving chairs if need be.
Nothing. Just a bunch of nothing, and it's starting to get on my nerves.
I know I can just sit here an accumulate (a very low) salary, without lifting a finger, but I can't help but feel guilty when people look into my office and see me doing nothing.
I can hear them thinking "what's this guy hired for? He just sits there costing us money, doing nothing", and I can totally agree. Personally, I wouldn't have hired an extra hand during the summer, since there's nothing to do, but I'm still grateful for the job opportunity, since I really need the cash. REALLY need the cash.

I guess I'd be more ok with this if I had a slicker's attitude towards life, but I don't. I'm for efficiency. I'm for getting the job done and moving on to the next thing. Being impatient doesn't help my situation either.
Later this afternoon I'm scheduled to install some PCs at our new location, and even though this is serf work, I'm looking forward to the opportunity to do anything at all.

All the while, I'm trying to figure out new software schemes and finding ideas for applications to write that people might need, but so far I've come up with nothing.
I'll gladly put in double overtime on a hacking project, but when I'm just sitting there, I feel that I could just as well go home, if it wasn't for the money.

I need ideas regarding how to spend all this free time that I have, that does not include things like playing wow, because that would be too damn obviously a missappropriation of the company's time and money. Software project proposals welcome!

--Markus (bored) out (of his mind)