2. Used as an intensifying suffix.
3. Used as a suffix on names (see "J-Sauce" above) as either a) an homage, if you're giving the nickname to someone else; or b) a sign of how cocky you are, if giving it to yourself.
In senses two and three, can be replaced with sizzle
1. Guy 1: "I went crazy off the sauce last night and got with your mom."
2. Guy 2: (Shudders.) "That's weak-sauce."
3a. Guy 3: "Damn, Guy-1-sauce, that's bangin'!"
3b and 4. Guy 1: "Damn right! I'm Guy-1-Sizzle!"