Tom Cruise -- Happy 50th Birthday!!!

Sure, he's got some issues now -- his movie tanked, he's getting divorced -- but Tom Cruise is turning the big 5-0 today ... and he STILL looks like $275 million (minus Katie's share.)

Here's the actor as a 29-year-old back in 1992 (left) -- and over 20 years later, the new fiftogenarian at some event in June.

The question ...