Two Nifty Extensions for Firefox - Scribe and Spellbound.

Here's a nifty little plug-in for Firefox - Scribe. Its gives a much needed ability to save form fields (those boxes that you can type into on a web page, before you click the "Submit"). And the second one is spellbound which lets you check the same boxes for spellings.

For the IE users (argh!), there's a similar but free-for-personal-use types add-on called IESpell.