Attached is a bundle to implement kill (^k) and yank (^y) as close to the Cocoa/Emacs implementation as I've been able to get. I hope others can get some use out of it as well.
Using TextMate, I've had a terrible time trying to overcome years of muscle memory in using ^k to kill and ^y to yank. The same functionality is certainly available in TextMate, but I just can't make my fingers not expect ^k and ^y to work a certain way. Allan has mentioned that a Cocoa-like kill buffer is on his todo list, but I thought I'd attempt something to tide myself over until that arrives.
Some high-level things you should know about the bundle:
* It does map ^k and ^y.
* Like Cocoa/Emacs it uses a kill buffer totally separate from the standard Cocoa clipboard.
* I couldn't figure a good way to implement the kill buffer without using the filesystem, so that's what it does.
* In order to get the behavior as close as possible to a real Cocoa kill buffer, it's a great kluge of multiple commands and macros. That fact plus the fact that it uses the file system makes it sort of slow (I think certainly usable, though).
I hope folks find some use in it.