Is it possible to use remote desktop to connect to 2 different PC's behind an
ADSL router with a dynamic IP address from an ISP. I think the answer is no,
but am just checking. I can set port forwarding on the router to 1 of the
PC's but if I have 2, how will the port rule know which PC I wish to connect
to.

I have 2 users that wish to simultaniously connect to their work PC's from
home via Remote Desktop Sharing

I think I will have to get 5 fixed IP's from BT but obiously, the line cost
will increase....

Any confirmation on this would be great.