Reimbursement

You spent your own money, working on the company's time, to buy that case of Rat-Away (and you're not the company exterminator; in fact, you're the company's computer network ops person, tired of having to reboot your system courtesy of fried rat du jour).

So you spent $82.95 plus tax on Rat-Away. You brought back a receipt to the kindly old HR lady, and she reimbursed you for the money you paid to put Mickey to sleep for good.