Just found Browser Chooser and it's great!
Solves my long-time annoyance with various programs launching a web browser for some reason (opening Help from the menu, for example, or after installation opening a "welcome!" page!). I usually have dozens of tabs open so if the default browser
is not already running, it takes ages to start it, load all the tabs and finally show the page I probably didn't want to see in the first place!
One feature I would like to see in Browser Chooser is to be able to set one browser as my "favorite", and have BC check if that browser already running and automatically open urls in that browser without asking. If my "favorite" browser
is not running, then BC would prompt me to select one of the browser choices.
That way, if some program or e-mail link wants to open a web page, I could select IE instead of accidentally launching my 50+-tab multi-hundred-megabyte takes-5-mins-to-get-up browser.