Let's say I'm searching for questions on stackexchange.com, and have accumulated a number of tags in my search criteria (ex: all questions tagged "java", "jvm", and "struts"). Now I want to remove one of those tags from my criteria while preserving the rest of my criteria (remove "struts" and search only for "java" and "jvm" now). Is this possible to do from the stackexchange interface?
On the search results page, the search box in the top right corner contains the search criteria that you used (even if it was automatically generated by clicking tag links). I believe the best you can do right now is edit the search field to remove the tag you no longer want, and then submit the search again.
There doesn't appear to currently be any way to remove a tag in the same way that the side bar allows you to add them.
Edit: I updated the SE Modifications userscript to add buttons next to tags on the results page that allow you to remove or term-ify tags (quote the text) and resubmit the search, if you're interested in that. I plan to extend the functionality a bit farther, but for the moment it does at least cover this use case. Here's a screenshot of what it looks like: