Log: allow searching using logical operators

I would like to be able to filter the log using logical operators. For example, I'd like to perform searches like:

"crash +startup +UI"

"settings -frontend"

"<my user name> +merge"

etc.

Basically I want to be able to combine search terms using logical "and" and "not" operations, so that I can filter the log down to only the specific commits I'm interested in. 

Currently this is not possible, and makes it difficult to find a particular commit. For example, searching for my user name might turn up thousands of commits, but searching for my username AND "crash" will filter that list down considerably.

This is a simpler version of a far more complex request that has been open since before SmartGit had this UserEcho site (see Log: filter query language [SG-10517])