Sniper Crouch Toggle
Ever get tired of holding down they crouch key to lay low while waiting for your target? Try this crouch-toggle script -- pressing 'x' once will keep you crouched until you press it again.
alias +spec4 "doduck"
alias unduck "-duck; alias +spec4 doduck"
alias doduck "+duck; alias +spec4 unduck"
bind x + spec4

Sniper Charge-Toggle Toggle
If you like, you can make a key toggle between 'sniper mode' (described above) and ' regular attack' with this script (change 'y' to the key you want to toggle sniper mode and change 'x' to your normal fire key or button)
alias snipeon "-attack;wait;bind x chargeshot;echo SNIPER MODE ON; wait;
bind y snipeoff"
alias snipeoff "-attack;wait;bind x +attack; echo SNIPER MODE OFF ; wait;
bind y snipeon"
bind y snipeon

Sniper Charge Toggle
Tired of holding down the fire button to charge up your sniper rifle? This alias creates a special sniper rifle fire button that works by press (and release) once to start charging (laser sight appears and you are slow moving), press (and release) again to fire:
alias chargeshot "+attack;wait;bind XX fireshot"
alias fireshot "- attack;wait;bind XX chargeshot"
bind x chargeshot

Sniper Charge Audible Timer
This script is for those who want to make sure the sniper rifle is fully charged . Press x to start charging and the audible countown to max charge. When you're ready, click the left mouse button (or whatever you change 'mouse1' to) to fire.
alias timer "speak seven.six.five.four.three.two.one"
alias charge "+attack;wait;timer;bind mouse1 fire"
alias fire "-attack;wait;bind mouse1 +attack"
bind X "charge"

Sniper Quick-Switch
Press and hold x and you go into sniper mode and start charging the rifle. Release x and you fire and go back to normal mode with your last weapon back.
< font face="Courier"> alias +snipeon "tf_weapon_sniperrifle; wait; special; wait; +attack"
alias -snipeon
"-attack; wait; special; wait; lastinv"
bind x "+snipeon"

Sniper Slow Zoom
If you prefer a slower zoom mode try this.
// Slow Zoom
alias sview1 "fov 15; wait"
alias sview2 "fov 30; wait"
alias sview3 "fov 45; wait"
alias sview4 "fov 70; wait"
alias sview5 " ;fov 90; wait"
alias sview6 "fov 110; wait"
alias zoomin " sview5; sview4; sview3; sview2; sview1"
alias zoomout "sview2; sview3; sview4; sview5; sview6"
alias +snipe "zoomin; crosshair 2; sensitivity 5& quot;
alias -snipe "sensitivity 15; crosshair 2; zoomout"
bind a "+ snipe"
Note that the key must be held down to remain zoomed in.

Circle-Strafer
This is for running a circle around the enemy, one key for left circles (Y) and one for right circles (X) so you can focus your attention on getting a frag.
alias +circ_l "+moveleft;+right"
alias -circ_l "-moveleft;-right"
alias +circ_r "+moveright;+left"
alias -circ_r "-moveright;-left"
bind "X" +circ_r
bind "Y" +circ_l

Fire and Prime
This script allows the player to fire his/her weapon and prime a grenade at the same time with an audible countdown by pressing "x". When the player wants to release the grenade he/she just needs to stop holding the "x" button.
alias +grenattk "+attack; +gren1; +gren2; primeone; exec timer.cfg"
alias -grenattk "-attack; -gren1; -gren2; throwgren"
bind x +grenattk
//In timer.cfg (make a new config file in Half-Life/TFC):
speak "three _comma _comma _comma two _comma _comma _comma one _comma _comma _comma zero"

Grenade Primer
With this script you can press the default grenade keys (f, g) once to prime and again to throw. This is useful for timing grenades to go off as soon as they land.
bind "f" "grenonethrow"
bind & quot;g" "grentwo"
alias grenone " ;+gren1;wait; bind f grenonethrow"
alias grenonethrow "-gren1;wait;bind f grenone"
alias grentwo "+gren2;wait; bind g grentwothrow"
alias grentwothrow "-gren2;wait;bind g grentwo"

Please Note: I found these scripts at various sites, none of them were made by me. I have not tested all of these scripts so I am not sure how good each of them work. Cut and paste these in your autoexec.cfg or sniper.cfg files.