Counter-Strike Cheats

Arctic sniper rifle - givespaceweapon_awp
Auto-aim with sniper rifle - sv_aim
Adjust gravity - sv_gravity <-999 - 999999>
See and fire through walls and objects - gl_zmax <0-9999>
View other players' frags - cl_hidefrags 0
Faster forward motion - cl_forwardspeed 999
Faster backwards motion - cl_backspeed 999
Faster side motion - cl_sidespeed 999
Level select - changelevel <map name>
Weapon select - give <weapon name>
Auto-reload enabled - +reload
Auto-reload disabled - -reload
Change skins - skin <skin name>
See things brightly without flashlight - lambert -1.0001
SetC4 timer - mp_c4timer <-1000-1000>
Hyper auto-aim enabled - sv_clienttrace 999999999
Hyper auto-aim disabled - sv_clienttrace 1
Get $16,000 - impulse101
Splatter bones and body tissue - impulse102 (or impulse202)
Set freeze period at the start of rounds. Set to 0 to disable (default is 6) - mp_freezetime <#>
Set maximum length in minutes a round can last (default is 5) - mp_roundtime <3-15>
Toggle auto-help hint messages (default is 1) - ah <0 or 1>
Toggle crosshairs in observer mode (default is 1) - cl_observercrosshair <0 or 1>
Toggle flashlight use (default is 1) - mp_flashlight <0 or 1>
Toggle footsteps (default is 1) - mp_footsteps <0 or 1>
Whiten all surroundings at 800x600 resolution - r_lightmap 1
Turn off textures - gl_picmic 3

Use one of the following entries with the 'give' code to get the corresponding weapon. 

AK-47 - weapon_ak47
Benneli xm1014 - weapon_xm1014
C4 - weapon_c4
Colt M4a1 carbine - weapon_m4a1
Commando - weapon_sg552
Fn P90 - weapon_p90
Glock 18 pistol - weapon_glock18
HE grenade - weapon_hegrenade
M3 super shotgun - weapon_m3
MAC-10 - weapon_mac 10
MP5 - weapon_mp5navy
Para - weapon_m249
Scout - weapon_scout
SIG p228 - weapon_p228
Steyr Aug - weapon_aug
Desert eagle - weapon_deagle
Usp.45 pistol - weapon_usp

Use the following skin names with 'skin' code:

Arab - arab
Arctic - arctic
GSG9 - gsg9
Guerrilla - guerrilla
Hostage - hostage
SAS - sas
SEAL - seal
Terrorist - terror
VIP - vip