There was a guy from Sic* that either had a sick machine or he was cheating. He was doing WU in 5 seconds and getting paid 667 credits. He had 22000 of them that the admin invalidated. The admin ran the WU that were turned in during that period back through the validator to check them so you got bonus credits.

If that guy (Butterfly Effect*) was your wingman then the WU got marked "invalid" on your account as well. I lost 33 WU that way.