After installing Half-Life and then Counter-Strike, I downloaded more than 400 megabytes of stuff (patches for the above two, and DoD, and various map packs). Although I am still having problems getting into my ISP's fastest servers (something, I suspect, has to do with the compulsory Cheat-Death anti-cheat program), I managed to find a working CS server among them.
After an hour of so of playing, I have to admit that it's pretty fun. The fact that I had a pretty good morale booster towards the end (me somehow getting a 2/5 win rate as a Tango against two CT, one who previously seemed invincible) was... Beneficial
[/rant]