+2  A: 

It's being implemented for Emacs already. You can download it from here: http://www.emacswiki.org/emacs-en/ThingsEmacsCannotDo

You also find a screenshot there.

That's nice but I ain't a Emacs guy, any other alternatives?
Alix Axel
+2  A: 

Rockscroll for Visual Studio and JEdit has it. Links in this answer.

I'd love it for TextMate (my day-to-day editor) though.

Jon Hadley
Jon: http://eric.lubow.org/2010/mac/textmate-minimap-plugin/
Kenneth Reitz
+3  A: 

I have started working on a TextMate minimap plugin. Have a go, if you want. I would appreciate any feedback! It can be found on http://julianeberius.github.com/Textmate-Minimap/

Julian Eberius
I'm not on Mac, @Jon Hadley might find it useful though. =)
Alix Axel
Oh, yeah, my commment was intended for him ;-)
Julian Eberius
Link is wrong, this works:http://github.com/JulianEberius/Textmate-Minimap
Jon Hadley
After some slight confusion trying to find it after installation (it appears *under* the project drawer), it seems to work well - great stuff Julian.
Jon Hadley
+1  A: 

There is also a vim plugin. Its called CodeOverview and requires the .NET framework >= 3.0 and vim with a version higher or equal to 7.2.

Here is a short demonstration video on youtube: http://www.youtube.com/watch?v=vQqeAk__vvE

Gregor Müllegger
A: 

on doze rored had one (for rails only, really)

rogerdpack