VNC, UltraVNC - Free Remote Control Tools

VNC is a great free remote control program. It's open source, works well, is multiplatform, has a minimal install, and more. The homepage of the "original" project is now at http://www.realvnc.com/. For many years I used UltraVNC for it's built in file transfer and the available mirror driver (which was relatively awesome at the time). I now use TightVNC as it seems to have caught up feature wise to UltraVNC and seems to be under more consistent development.

A little slow, or rather, bandwidth intensive than PC Anywhere. Newer and alternate versions have some new optimizations, see UltraVNC.
Password syncing can be weird. Potential way to sync passwords picked off the VNC mailing list:
- If you'd rather do it by hand, just manually copy the password key from:
  - HKEY_CURRENT_USER\Software\ORL\WinVNC3 to
  - HKEY_LOCAL_MACHINE\SOFTWARE\ORL\WinVNC3 and
  - HKEY_LOCAL_MACHINE\SOFTWARE\ORL\WinVNC3\Default.
VNC over HTTP - http://www.ergotech.com/misc/VNCProxy.html
List of various flavours of VNC and some add-ons and FAQ's. Nice. - http://faq.gotomyvnc.com/
http://www.liquid-reality.de/main/projects/esound - a esound binary for Windows and some instructions on how to export sound from Linux and listen to it from a Windows client. It probably doesn't work, and I haven't tried it yet.
Listen mode uses port 5500 by default - see: http://realvnc.com/winvnc.html
To start an outgoing listen mode connection from the command line: "c:\Program Files\RealVNC\VNC4\winvnc4.exe" -connect xxx.xxx.xxx.xxx
Win2VNC uses VNC to use multiple computers as if they were dual screens -- http://sourceforge.net/projects/win2vnc/
Some more options.... lots of free as in beer ones - http://ask.slashdot.org/story/12/08/19/2121204/ask-slashdot-options-for-foss-remote-support-software
ChunkVNC is a module that optimizes the end user experience like TeamViewer or Join.me - you need to provide a Internet accessible machine for relaying - http://forum.ultravnc.info/viewforum.php?f=50
TigerVNC, used in Fedora, is based on never-released TightVNC 4 code. http://sourceforge.net/projects/tigervnc/

UltraVNC Notes

Apparently, UltraVNC 1.0.3 and above you filter IP addresses by ultravnc.ini (not registry) (!) - "AuthHosts=" - http://forum.ultravnc.info/viewtopic.php?t=13901
This was announced not too long ago: http://ultravnc.sourceforge.net/ - a lot of useful features. I've finally tried this personally. It is awesome, and I have no longer any reason to use PcAnywhere (well, modem support I guess). UltraVNC has video hooks driver to get accurate and superfast updates. It also has file transfer, screen blanking, and other stuff. Go use it.
Update: Over the years, UltraVNC seems to have lost developer support, I moved new installs to TightVNC around 2018. Separate note for TightVNC.