Negative Tag Filtering

[mikeisenberg]

Title
Negative Tag Filtering

Short, concise description of the idea
Filter entries in such a way as to exclude entries with a particular tag.

Full description of the idea
I use LoudTwitter to publish content once a day to my LiveJournal. I'd like to be able to tag all of those posts "twitter" and then have a way to link to all the posts not tagged "twitter" so that I see only those posts that I've actually written for LJ. The only way to accomplish this currently would be to tag all of the non-twitter entries as "non-twitter," and it seems counterintuitive and cumbersome to have to tag posts with descriptions of what they are not. Adding negative tag filtering seems like it would make the tag system more robust without creating any more system strain than simple positive filtering.
An ordered list of benefits

• Allow an easy way to filter out "noisy" posts.
• Allows a simple way to keep posts public while choosing not to display them.
• Generally makes the tagging system more robust and useful.

An ordered list of problems/issues involved

• I don't know how the code currently works so I don't know how hard it would be to implement.