Tripod head for Macro photography

I have an inexpensive tripod but think it will be fine with a better head. Anybody know of a tripod head that lets you move in and out to fine tune manual focus in 1:1 mode.

Kind of like a focus rail but built into head?

Not that I'm aware of, and if there was I'm sure it would be pricey.

Seems like you're looking for a focusing-rail. RRS (Really Right Stuff) have them.

Edit: Whoops. You already know about those. Well, a ballhead would be practical, to quickly get into position.

No rail but one could be probably mounted. The Manfrotto 410, a geared head.
If I was shooting a lot of macro, that would be the head I would get. Actually if it wasn't so heavy I would have bought that instead of the Markins M10.

I second the vote for a geared head. It's on my wish list. I have a ballhead currently, but it has too much give when trying to fine-tune for macro.