We've been using Logmein Hamachi
(free for up to 5 users on a single network) to create VPNs along with Windows Remote Desktop
to take over systems remotely. There is no screen sharing with this setup, however you can log in to a system and take it over completely using RDC. If you need more capacity and features it costs only $29 anually for up to 32 users
on a network.
For simple remote screen sharing we've been using the free version of join.me
, which has worked pretty well so far.
I'm always interested in finding alternatives, so if anybody has any other solutions, reviews or experiences they would like to share I'd be interested in hearing about them. Thanks, Scott.