Arduino RGB LED controller

Hi folks, I am thinking of making something which requires an LED controller. I'm looking for something small, which will allow me to do this. Now I know we have arduino micro or nano, small and dirt cheap, but, is there a smaller controller which may do the job? My thought is a button controlled LED, every click changes colour, or cycles through the colours automatically,but I'm looking at really small scale.

I need something that can run for a good while with little power drain on batteries. Which can power multiple LED's.

Any ideas?

Check these out

https://www.sparkfun.com/search/results?term=cycling+led

forum adds some extra characters to start & end, just delete them.

Thanks fr the pointer. Sadly most of those controllers are too bulky for what I am trying to achieve.