When using a Cocoa app, why not just select the text you want to copy, then select "Services -> TextEdit -> Open Selection"? TextEdit will launch and a new document will be created with your selection. Services work in any Cocoa app, but unfortunately, not with Carbon - a big problem, since the vast majority of apps are Carbon, including IE and Office.
[Editor's note: Services in Carbon applications are now technically possible, I believe. I had thought BBEdit was one of those apps, but that may not be correct...]

