I got sick of maintaining a number of profiles in MySQL Query Browser,
so I wrote a URL handler for it. It takes URLs in the form of
mysql://username[assword]@host[ort]/database, and fires up MySQL
Query Browser for you. You can type that URL in your browser window,
in the Start > Run dialog, in your explorer address bar, whatever.

If you have need of other features (I was thinking about maybe adding a
mysqladmin:// handler for MySQL Administrator) or encounter bugs, let
me know The code assumes you have MySQL GUI Tools installed so that it
can find the location of MySQL Query Browser in the registry, and it
assumes you have access to write a registry key to HKEY_CLASSES_ROOT.

Source, binaries, and instructions are available at
http://tgmayfield.com/projects/mysql/