A lot of people like URLwell, but it suddenly disappeared from where it used to be (Enigmarelle Development). I’m hosting it here until somebody asks me to stop.
Some information from the old MacUpdate page:
URLwell is a great place to stash all those URLs you find in emails or on web sites that you just don’t have the time to look at now.
Just drag the link to URLwell’s menu bar icon and it’s saved. When you look at it, it can be removed from the list, or if you prefer, it’ll just be checked off to mark that you’ve seen it, and remain in the list.