Mark Cuban -- His 'Shark Tank' Investment Is The Cat's Meow!

Mark Cuban really does have the Midas touch -- his $25,000 investment into an online business that produces stick figure drawings of cats (yes, really) is actually proving to be a moneymaker ... and the guy behind it can't keep up with the demand!

Steve Gadlin's appearance on the ABC show "Shark Tank" aired just this Friday. For the uninitiated ... entrepreneurs go on the show seeking investments from a team of business "sharks," such as Cuban.

The Dallas Mavericks owner pledged $25k to Gadlin in return for 33% of his business. Within 30 seconds of receiving Cuban's blessing, Gadlin tells TMZ, his site crashed.

Gadlin tells us, he's gotten over a thousand orders in the past few days, where before he averaged between 10-40 a week. Gadlin charges $9.95 for his customized cat drawings ... and they only cost him about $0.63 in materials.

He says he's going to take a week off from his real job as a web developer to catch up with the demand.

We talked to Mark Cuban, who said "[Steve] is the master of the bizarre, which means we will be great partners. He comes up with ideas that sound crazy but make perfect business sense," adding, "I'm fired up to work him with."