I've been having a real problem with CS:S lately where the game is in the process of loading a map, and the progress bar stops at the mid-way point, during 'Loading Resources.' I've had to run the game in windowed mode just so I can close the application once it's frozen instead of force-booting the machine. I've had this problem once with Half-Life 2, but I haven't fired up that game in about a week; I should probably test that game too.
Rebooting seems to be the only way to solve the problem. From what I've seen (I have no idea if this is a simptom or a coincidence), leaving the computer idling for ~1 hour and trying to load the game will result in this problem.
I've done the regular thing; Verify and defrag the GCFs, deleted ClientRegistry.blob, and restarted Steam, all to no avail. Can anyone help me out? :