One of the newest items in my personal toolbox is the Linkwad extension for Firefox. I tend to have a whole lot of browser tabs open at once — if you're not familiar with tabs, that's essentially a stack of open browser windows. For me this is a great way of dealing with a set of search results: just open all the results that interest me in a set of tabs, and open any other related links in additional tabs; then work my way through the tabs one after another.
That's great if you can make it through ten or twenty tabs in one session. But what if you spend an hour finding a bunch of web sites you want to browse through, and run out of time to review them? Linkwad lets you store a whole set of open tabs for later reference and retrieval.
Once you install the Linkwad extension you need to register on the Linkwad site before you can save any tab sets. Once you're registed and installed the Linkwad toolbar all you do is hit "save" to store a tab set — you can name it and describe it for future reference, and you can even share your tab set with other Linkwad users.
Linkwad is a handy way for lateral browsers to manage a lot of related web sites across multiple browsing sessions. Well worth an install.