Square Enix has now added Lara Croft and the Guardian of Light to their list of free game offerings on CoreOnline. You can hop over there, install an applet (if you haven't already) and start exploring ruins at no cost directly in your browser. Isn't the internet neat?
I thought this was a fun little game made absolutely wonderful with a partner in cooperative play. If you haven't taken an opportunity to look at it before now, I'd recommend you give it a shot.