Logmein is a M$ Application that allows you to remotely control your computer, even if your computer is behind a firewall, or NATed. Is there a linux application that can do this ?

Yes. but the answer would be complicated (it depends on what exactly you want).
For text login, ssh is good. For graphical login, XDMCP or VNC are good. ssh can also forward a graphical session.
If the solution you choose has to use a specific port, you must setup a tunnel. And if you have a security risk, you can use ssh to make the tunnel (and encrypt it).

Yves.

Am I able to connect ot my PC through XDMCP or VNC WITHOUT any additional configuration on the server ? I must add that I'm on a private network, my IP is like 10.10.0.5, and our network server does SNAT in order for our network to access the internet ?

XDMCP is allowed if your X greeter is accepting them. If you use GDM for example, you can graphically configure it (just say: accept XDMCP) from the login screen. On the client PC, you would run something like:
X -query 10.10.0.5 -once

VNC is much the same except that the VNC server just has to be running, that's all.

Now, each of those two uses a different port, which may be different still, than the one you're allowed to use (due to firewall); in such a case, you have to either configure client and server to use this port, or use a tool that will tunnel through this port (ssh for example).

Yves.

does anyone know of an logmein clone that i can log into from a school pc (no special apps or ssh please!)

hi
i have a router and my pc is behind the router.
now i have enabled services on my computer like ssh, vnc, http etc. and i want the computers outside my router to access those services.
but when i attempt to do this the router says no service available, i have tried following things
bringing down the router firewall, opening specifice ports in the router and forwarding requests on those ports to my computer, but nothing worked for me.
now if anybody can help me please let me know how do i do this.
it will be very helpful
regards
deependra
be openbysource

how to learn about wireless networking anybody kindly help me

we are having linux 9 there is option are there for wireless networking