Lil Wayne -- I Paid $1,000 to Watch Strippers Fight

Lil Wayne has seen so many strippers, he's now tired of watching them strip -- so last Monday, he watched them beat the crap out of each other instead ... and then dropped a $1,000 tip on the lucky winner.

Weezy hit up the famous King of Diamonds in Miami for its special fight night -- sitting above the ring like strip club royalty ... you gotta see the clip.

The chick in the purple trunks is the clear winner -- pinning the other stripper against the ropes with some nasty one-twos -- and moments later, Wayne rewarded her with a giant stack of singles ... amounting to $1,000.

Several sources inside the club tell TMZ, Wayne spent three hours at KOD that night ... and dropped around $30,000 over the course of the evening.