I heard an old trick to avoid overspending. Bookmark an item, and look back in a week. If you still want it, buy it!
I don't have that overspending problem, but I find it applies well to bookmarks. I clear it out once a week, it's a very fun chore. Looking back with a fresh mind, many things are not interesting to me, and those things that are, I can invest time in to look at.
Useful looking tools or programs, I usually file away permanently to another bookmark, because I find myself looking back there many months later :)