A recent comment posted on my RBTray review tells of a Vista/Windows 7, 32bit and 64bit compatible RBTray.
To quote the (new) developer "I made RBTray Vista/7 and x64 compatible, removed the application menu additions altogether, and fixed the small target on the minimize button with XP theming (that was not intentional BTW). It’s on my site and on the official RBTray SourceForge page as well".
This is probably my favorite minimize-to-tray app, if just for being so lightweight (about 1 meg in memory). It was also featured on my "Forty-Three of The Best Free Windows Enhancements That You Should Know About" posting.
Go here to read the original review, or here to download (~100K).
Version Tested: 0.41
Compatibility: Windows XP, Vista, Windows 7. Requires MS .NET Framework 2.0 (download 32bit, 64bit).

This’d be useful to me if it minimizes and app to tray with a hotkey. For example, Win+Ctrl+N sends the foreground app to the tray.
You might like PowerMenu. Similar in size 146kb and portable. Also includes, ability to set system priority, window transparency and always on top all from right clicking on a window.
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(reviewing RBTray version 4.1)
This program is a simple shell extension that does one thing and does it well,
Just start the EXE and it’s instantly hooking into your Windows shell.
*** IT DOES NOT REQUIRE “MS .NET Framework 2.0″ ***
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(from the “readme.txt” file by the author)
Installing ———————————————————-
Extract the 32-bit or 64-bit binaries (depending on your OS) to a folder, e.g.
C:\Program Files\RBTray. Double click RBTray.exe to start it. If you want it
to automatically start after you reboot, create a shortcut to RBTray.exe in
your Start menu’s Startup group.
Using —————————————————————
Right click on any program’s minimize button to minimize it to the tray. To
restore, single-click the program’s icon in the tray.
Exiting ————————————————————–
Right click on any tray icon created by RBTray and click Exit RBTray in the
popup menu. Or run RBTray.exe with the –exit parameter.
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