Yeah, the ShamWow is the thing that soaks up stuff:
http://i180.photobucket.com/albums/x98/vrykyl250/SHAMWOW.jpg
I don't know who sells the ShamWow, but it isn't Billy Mayes. Billy Mayes is the guy with the beard that sells the OxyClean stuff:
http://www.princeroy.org/Billy_Mays.jpg
As for one-upmanship, it's when someone does something intentionally as a means of making you feel inferior so that, in comparison, they will feel superior in the conversation, or "one-up" you in the exchange. I'll break it down for you as I saw it in this thread:
1. 00BlackWS6 comes in with a shitty intro (e.g., "Hey, I'm 20 and from Columbus and here's a picture of my car as it would appear during an earthquake").
2. People call him out on his shitty intro (e.g., "Hey, your intro fucking sucks").
3. 00BlackWS6 clown guy then comes back with, "Hey, George was my cousin - now don't you all feel like jerks for making fun of me?" This is the one-upmanship: 00BlackWS6 McDouchie plays the "George card" as a means of trying to make everyone feel bad (i.e., inferior) for giving him a hard time. Fact is, he could have said George was his cousin from the very start (and probably should have), but he instead opted to withhold that information and reveal it at the very moment he wanted everyone to feel bad for him. That, in my opinion, is one-upmanship; the OP wanted to "one-up" everyone in the exchange and used his deceased cousin to do it. He may not have intentionally meant to do it (and, from the looks of it, he doesn't have enough neurons to be that clever), but he did it nonetheless, and it's annoying.