Look at my WRT Info thread in the Developers sub-forum. There are links to several sample apps Nokia has endorsed as sample code, including AccuWeather, Stew (Twitter client), and some others. There is also a widget written by a HOFO member (Micky) to setup PixelPipe as a conduit for Share Online. I've also written a Stitch Counter (for knitting) but it's not production-ready yet, as it doesn't save the current state. I hope to have some time to finish it up next week.
Mosh also had a few, but I think Mosh is no more. All you had to do was search for 'widget.' Most of them sucked but a few were OK.
In other news, we may be going to the Chicago flagship tomorrow and if we get to play with the N97 we will be sure to post our thoughts (and maybe some pics and/or video).