You will not be punished for joining a server running "achievement_idle" and leaving your computer on.
However, the marginal gain idling provides means that it's not a very effective way of getting items, especially if running your computer for that long means overheating.
Valve never "punished" idlers, only those who used the external program developed by Drunken_f00l to trick the steam servers into thinking they were in the game, connected to the server, when in fact, they were only connected to the server, outside the game.
For what it's worth, I believe Valve stated that ~1 hour a night was enough to get all your weekly drops.
Note: This answer's numbers have been updated with numbers from the client sizes. The server size is much smaller.
10.5GB is correct. Of this, 3.68GB are shared files from Half-Life 2 and Orange Box games. That leaves 6.82GB specific to TF2. This is a logical progression from the 4.85GB TF2 was at when update 119 was pushed a year ago.
Team Fortress 2 is split up into 6 distinct packages on the Dedicated Server side, totaling 5.8GB.
TF2 is split up into 11 packages on the client side, totaling 10.5GB.
The client packages are:
- team fortress 2 content.gcf - 3.95GB
- team fortress 2 materials.gcf - 2.84GB
- team fortress 2 client content.gcf - 27.5MB
- source 2007 shared materials.gcf - 985MB
- source 2007 shared models.gcf - 148MB
- source 2007 shared sounds.gcf - 2.26MB
- source materials.gcf - 1.02GB
- source models.gcf - 449MB
- source sounds.gcf - 975MB
- orangebox media.gcf - 7.55MB
- multiplayer ob binaries.gcf - 155MB
I can break down the TF2 Content package further. The only 5 directories larger than 25MB are:
- bin/ - 40.1 MB
- maps/ - 2,364.5 MB
- media/ - 620.7 MB - Movies that play the first time you play a map
- models/ - 426 MB
- sound/ - 901.1 MB
The problem is that most things in Source games are uncompressed. All non-music sound files are 44Khz, 16-bit mono wav files. There are also 11 compressed music files that are 128kbps 44Khz 16-bit Joint Stereo mp3 files.
Map files are stored uncompressed, despite Source understanding the Bzip2 compression algorithm. Valve ships 51 maps files: 48 are multiplayer maps, 2 are Training maps, and 1 is the Item Test map.
The average map size is 47.6MB... unless you take out the training and item test maps, then the average size is 49MB. Arena maps are typically smaller in size, while multi-stage maps (like Dustbowl, Goldrush, etc...) are typically larger.
Every new hat in the game adds a number of files. It adds 4 models, possibly 1 physics file, 2-4 material files, and 1 backpack icon file. As far as I can tell, these files are all fairly small... they add up to around 2MB for the Portal 2 Pin.
Best Answer
The servers on Valve's end that are used for backpack information and/or trading occasionally go down or are under heavy load. When this happens, TF2 and Steam cannot access your backpack at all.
If this happens, it's likely that your items may be currently untradable and/or your entire backpack will be completely inaccessible, meaning you'll be unable to trade, and - if you're playing - your class loadouts will revert to using the stock loadouts for a period of time.
Whilst there is no guarantee what time they may come back up, you can also check on TF2Lists for the current status of the servers. If they are currently down, your options are limited. You can try:
* I cannot vouch for the reliability of this method