It's already implemented I guess, it's called ""scroll_past_end". add this to your user preferences and you're good to go: 

you can aslo use command+T. I use this one since it's easier and similar to what I've been using in the past

I'd like to have it but as a plugin not built in

+1, I had the same problem in my markdown files, where I turned off line numbers and gutter

love to see this feature

I can confirm that this actually happens. to see the problem I've attached a screenshot of ST2 and Texmate on a Samsung SyncMaster with the same color-scheme and font

I still don't see bold and italic FontStyles in my markdown files. I checked and my textmate theme has already fontStyle definitions. I'm using dev build 2162 on Mac OS 10.7. 

Tabs are now following the color scheme, it would be really cool if sidebar and other UI elements can also follow the color scheme. can't wait to see this feature in future.