I have a first implementation of FFSS.exe which is Firefox Session Save. For now the hotkey is hard wired as Control-Shift F10. The idea is you have FF open with multiple tabs. Make it the active window and hit the hotkey. It uses macros to change tabs and copy the addressbar url to the clipboard, then save the list to a text file. You can then open that text file as a set using Browser Bunch.
For now the text file name is hard wired.
The zip attachment has FFSS.au3 AutoIt3 3.3.8.0 source code. Compiled .exe and custom icon.
edit: Clipboard text content before the hotkey hit is saved, then copied back to clipboard after URL collection.
edit2: updated to 1.01 contents of the text file are overwritten. Rename the file to use with Browser Bunch. I'll probably add an option to open a SaveFile Dialog and change the hotkey in the future.
edit3: now that this seems to work I think I'll add it to the Browser Bunch download package. To create a text file of URLs the user will be able to hit the hotkey on Firefox and save it to a text file with FileSaveDialog. Then it can be opened with Browser Bunch either using SendTo menu or in Windows Seven, pin the file to the taskbar Browser Bunch icon. Once the set it created it can be opened in any browser supported by Browser Bunch.
edit4: Browser Bunch download now includes the latest version of FFSS in the zip file.
http://www.favessoft.com/downloads.html