Is it possible to kill yourself with a throwing knife in Modern Warfare 2

Modern Warfare 2 (in fact all the Infinity Ward / Treyarch COD games) are based on a heavily modernised variant of the Quake 3 engine.

This means that the server (and other clients connected to it) can send config data files to your machine and pass on weird settings.

There was an exploit some dude did on a hacked X360 version of the 1st Modern Warfare whereby he created a a "viral" config that had low gravity, extra weapon damage for certain weapons etc. that would pass from console to console.

AFAIK these transferred config settings are transient and will go when you close the game, but it is entirely possible that they could persist on the PC version.

Also, since this is all accomplisghed just by sending data about it's pretty unlikely (but not impossible) that a hacked server would use this to inject executable code into your PC.

In C:\Program Files (x86)\Steam\steamapps\common\call of duty modern warfare 2\players there is a file called config_mp.cfg. Open it with Notepad/Wordpad. There are two values you must tweak, namely cg_ScoresPing_Interval and cg_ScoresPing_MaxBars. You have some discretion with the former; the latter should be set to 10. I use the following:

seta cg_ScoresPing_Interval "30"
seta cg_ScoresPing_MaxBars "10"

This is how it works. Where the number of bars shown is >1, the ping lies in the following range:

(maxbars-shownbars)*interval to (maxbars-shownbars+1)*interval-1

For an interval of 30, this means:

• One bar: >270 ms
• Five bars: 150-179 ms
• Nine bars: 30-59 ms
• Ten bars: 0-29 ms

Knowing this, you may want to assign cg_ScoresPing_Interval a lower value.

There are also tools available that purportedly unlock the hidden developer console, with which you can enable a numeric ping display. Personally I wouldn't trust programs of this nature because of the small risk that they may be malicious or result in a VAC ban. With that said, you can read about one here.