Marvelous! I'd been using a modified copy of the Aardvark extension for Firefox since Firefox was upped to 1.5 as the 'real' Aardvark broke, but now Karmatics have released an updated Aardvark for Firefox 1.5 and my life is complete again (note: possible exaggeration present in text). For those that don't know, Aardvark is an extension for Firefox that allows you to highlight block-level elements in a page one at a time by mousing over them. The element gets a red border and tag describing the type and ID/class values. You can then widen/narrow the selection as well as isolate/remove it, or play with colouring. The extension is of unimaginable use in developing websites as it helps you track down hard-to-find CSS problems, or just have a quick look at how someone else has put a site together, so get it now.