Firefox extension for website interaction recording and repetition

Does anyone know of a firefox extension, or some other tool, that enables you to 'record' the interactions with a website, and then play them back, as a way of testing a website?

From stackoverflow Steve M

• iMacros

  From eplawless

• Selenium:

  http://selenium.openqa.org/

  From Kevin Dente

• Watir

  From Kevin Goff

• http://code.google.com/p/tg4rb/

  TestGen4Web is a Firefox extension that records user actions on Firefox and generates XML code describing such actions.

  TestGen4Ruby (tg4rb) translates the XML output from TestGen4Web into Firewatir code.

  FireWatir then runs this code and replays the actions recorded by TestGen4Web.

  From Željko Filipin