Came across gobootstrap.com - pretty nice
If you select a link then drag and drop it over the "New Tab" toolbar button in firefox, it opens the page in a tab in the background. Nice huh?
I knew you could drop it over the address bar, but I never wanted to leave the current page so I rarely used it that way.
Of course you have to have the "New Tab" button active in your toolbar, which I've always had since phoenix, and I wonder why firefox doesn't come with it active by default, but I digress...
I totally agree about the "New Tab" button being up by default. It's the first thing I do when I'm on another computer without it.
Edit: But that would only work if it was an actual link. Plain text doesn't work obviously.