Review for Mail and Save Tab URLs by PhilD13
Rated 4 out of 5 stars
Very flexible in how you can capture and keep or share proliferating urls. Has pretty much every possible feature you could want for saving or emailing links. Lots of options to tweak it the way you want, but simple and unfussy in its main purpose.
One star off, because some versions place ads at bottom of web pages, which can be annoying.
To create your own collections, you must have a Mozilla Add-ons account.