A few days ago, I had written about a service that would help tracking URLs posted on twitter. I had barely started working on it when a friend told me about tr.im. It is a URL tracking service with statistics.
Apparently, this can also be used for the other use cases - tracking on Orkut and forums. The redirect can be a simple transparent image placed in the forums or Orkut scraps. So, the next time you get a scrap from an annoying stalker, just add a transparent png using tr.im to the scrap that you send. You can also drop the image into all emails and forum posts that you make. This would give you an idea on how far your mail travels or how many people view your posts.
Though the service was written for twitter, you can use it for a variety of services.