"It should be noted that MSE is very small; the installer sizes range from just over 4MB to under 9MB. The installation is also very quick and the program's folder takes up only about 13MB. MSE sports a single tray icon (hidden by default in Windows 7) that indicates it is running. The software doesn't add any browser toolbars, desktop gadgets, or additional bloatware during installation."
Free and lightweight? Sounds like it's worth a try.