I've enjoyed Windows Live Writer as a blog editing tool for a while now (in fact, I think all of my blog entries have been written with it). WLW includes a nifty SDK (one that I haven't had a chance to play with yet) that enables add-in creation. Leo Vildosola created it, based on the more recent plugin I used in fact.
This is the third code snippet plugin I've used (just started this one today, in fact) and it's definitely the best. It has some nice features; if you look at the previous post, you'll see that it enables code to be contained within a container element, so that long listings don't need to take up pages. Very nice. It also has a mini mode! What more could you want?
I need to make a stamp graphic or something that says "Rob's Stamp of Approval". :-)