Yes. For about a year.

I take 5 g per day, mixed into a glass of milk.

I have more high intensity energy on the bike. In the gym, I get to the point where I've given all I've got, and after a couple minutes, I can do another set. I have more good ideas at work (as a software developer). All three of these effects are well documented among peer reviewed research.

For what it's worth, I'm a vegetarian, which means I don't get any creatine in my diet. It's in fish, poultry, and red meat.