DeskPins - DeskPins can be used to make any application topmost, that is, to keep it above all other windows.
Glass2k - Small little program that allows Windows 2000/XP users to make any window transparent.
PinWin - Download PinWin - Pin On Top for free. Pin any window to be always on top of the screen. PinWin is a minimal Windows system tray application that allows you to pin any windows to the top of the screen with one click.
GhostWin - GhostWin - Free Download -- Transparent Windows Utility supports Windows 2000, 2003, XP, Vista and 7
WindowTop - Easly set any window on top, just move the mouse to the top area of the window.
Feewhee - Feel the Wheel (Feewhee) is a tool that Microsoft apparently overlooked while making Windows.