Crystal Geyser water that has sat out all night on my desk. Warm & stale. Good thing I brought a fresh bottle with me this morning...but I have to wait until it thaws.
(We freeze the bottled water so it stays cold all day...I know, I know, there's supposedly some bad-ass carcinogenic things that happen when you freeze bottled water, but there are carcinogens in the friggin' AIR I breathe 24/7, so what's a bit more?
)