Cancel/Transfer Registration Link in Contact Dashboard
This feature makes sense, but doesn't currently exist.  However, I created an issue in the CiviCRM issue tracker for this exact feature.
I have a client who wants this, but I think they're going to run out of money before we can do it unfortunately.
The good news is that they DID fund the biggest part of this - until two months ago, the self-service cancel/transfer code was only accessible from the self-service/cancel page.  They funded me to move the code to a central location.  In the next couple of weeks, I intend to clean this code up further, at which point it should be under an hour's work to add self-service transfer/cancellation links to the user dashboard.