I’ve come across quite a few places that let you submit thumbnail images of your own site (such as MyBlogLog), but creating the thumbnail is never as easy as it should be. If you take a screenshot yourself you probably sit there messing with the dimensions and cropping the image until it is just right.
Thumbalizr is here to save the day! All you have to do is punch in a URL, choose weather you want it to snap just the screen (no scrolling) or the complete page (it scrolls to capture the whole thing), and then hit the "thumb it" button to send it off to do it’s job! What makes this service special is that their AJAX-powered interface show you the results almost instantaneously. They even provide 6 different resolutions of thumbnails, but if you don’t like any of those options just enter in a custom size:
There have been over 7,600 thumbnails created on Thumbalizr so far, and more are being done each day. I have a feeling that their stats are going to grow rapidly thanks to their new API. You can use thumbnails created by Thumbalizr by just providing parameters like this:
http://www.thumbalizr.com/api/?url=cybernetnews.com&width=500
If Thumbalizr already has a thumbnail in its database it will serve that up, otherwise it will be added to the queue and processed within 2-minutes. I would say that’s pretty impressive!
This is one service that has earned a spot in my bookmarks, and I highly recommend that everyone has this site saved for when they need it. 
Looks like quite a handy program. I made a little bookmarklet out of the URL you put up there. I set it to 800 as that seems like a good thumbnail size to actually be able to see the site, but you can change it quite easily by modifying the number after width=
javascript:void(window.open(‘[thumbalizr.com]+document.location.href+’&width=800′));
Oh, and do note that it takes a few minutes to work – you’ll just see a pause sign but after a minute either refresh or click the Go button again and you’ll see your image. I imagine this will get faster as the service grows.
Thanks! I’ve put that in my bookmarks. They do have a normal bookmarklet available under their tools section, which might be better to use since they don’t put the overlay on the bottom.