I'm in a remote area with limited Internet - 364 kbps down 128 kbps up shared among 20-30 office workers and over 100 residents. My computer can handle keeping tabs open in case I didn't properly solve the problem before, or if something similar crops up.
So, I have a lot of reference materials open on my desk, and I keep them open because finding the page I was on takes a long time, and loading that page takes even longer.
Some people might not know that it actually includes a feature specifically for this use case. If you start to type in a URL or page name similar to one already open in a tab, the awesomebar dropdown menu lets you jump to the already-opened tab.
That feature is actually broken on Ubuntu 10.10 / standard Gnome with multiple desktops - it tries to switch you to the appropriate tab but can't switch you to the appropriate desktop.
And I'm not sure I really like it anyway - when I re-type a URL I'm usually looking to reload it to grab a fresh copy. I tab-complete the address of my development server and Hacker News very often; anything else I don't usually know the URL off the top of my head, I just remember that I have such and such doc on such and such desktop.
So, I have a lot of reference materials open on my desk, and I keep them open because finding the page I was on takes a long time, and loading that page takes even longer.