MyCleener is a simple tool where it pulls the list of those you follow and shows you their last tweets. This gives you the ability to get an indication of someone no longer using the service or maybe gave up.
If you are having issues keeping up with the stream, trimming it down is a good way to start.
They do take your username and password but even go so far as to tell you:
- to change it before using the service if you want
- they store the data temporarily in a hashed for to be deleted
- or look at their stated source code yourself
I gave it a run and found out that that the longest it had been since a person I followed tweeted was over 7 months! Off the list they go