Want Firefox to look a little oranger? The Tangerinefox splashes a ‘bit of orange color onto your usually grey and blue(ish?) browser and uses themes based on the old Tango theme.
Everything in the theme looks very polished and does not bash you over the head with new colors and redesigns. The browser icons and backgrounds are a different variety, but are not too far fetched from the Firefox defaults.
Want to give Tangerinefox a shot? Go download it from the Firefox Add-ons website.