TechOpus.com

For some activities, it is hard to find a tool that will do the job and have all the features you need. This is not the case with To Do List managers. There are many good options for offline and online To Do list management.
My preference is to use one that automatically synchronizes items [...]

Two very useful extensions add-ons for Firefox are Gomita’s Scrapbook and Rob Brown’s Aardvark.  They are both well polished, elegantly designed, and very useful on their own but I find that they complement and complete each other.
Scrapbook allows you to save complete or parts of a web page to your local drive in managed collections. Your saved collections [...]