Griffin Technology has released a utility for enhancing the resolution on any current monitor, Super Res. Super Res is a set of software drivers that can improve monitor resolution beyond the standard settings. According to Griffin:
Griffin Technology, Inc. today annouced they have released Super Res, a free universal video resolution enabler for the Mac. Super Res has both a Control Panel and a Control Strip component that allows one to choose from nearly 50 different video resolutions on current Macs. Super Res enables a much larger range of video resolutions than are normally available. It works with all Macs since the PowerMac 7200 including G3s, G4s, PowerBooks, iMacs, and G4 Cubes.
Super Res is not only free but extremely powerful. It allows one to select resolutions of up to 1920x1440. It also allows the selection of bit depths. It is compatible with the built in video of all Macs as well as third party video cards. With Super Res you can now access ALL video resolutions supported by your video card or built in video not just the ones limited by your display.
You can download Super Res, and find more information, at the Griffin Technology web site.