lots of options, many pc's, you may want to check out VPN. linksys makes a very good router (i liked it so much i bought it!), WRV54G, it is a "roadwarrior" vpn router, and can open a tunnel from lan to lan. it uses "linksys quick vpn" as a client software, it is simple to use, and it uses IPSEC protocols which are very secure. Beats out microsofts PPTP and other methods for security. as for redirecting, the WRV54G has a built in redirector using DYNDNS www.dyndns.com , it is a free service you sign up to, and you dont have to install crappy broadcast software on your pc. you dont even have to set up static or port forwarding.
another pc to pc remote mgmt tool is VNC, and PCAnywhere. both are very popular and easy to use, the downfall is one pc at a time, instead of your whole lan. but it is a remote desktop. here yo need port forewarding on your routers settings.
PM if you want expanded answer on anything. this stuff i do all day long