Mine may not be epic but i was definitely saying "WTF!" Along with many other more colorful expletives.
Basically, I was playing modern warfare 2, in search & destroy, I walked into a room that holds a bombsite, I start making my way there, until I spot a claymore in the stupidest place Ive ever seen. In the middle of the fucking room. So I was like "hah lol noobs so gunna get pwned, cause im just teh pro ninja assassin." So i maneuver to be on the left of the claymore with like 5 metres between it and me, until it randomly explodes for no reason and kills me, it wasnt facing me, I was halfway across the room but i still get ballbearings up my anas. "FUUU.."