xBox_gamer1, have you got pranked up before? Like, someone drives up to you and tells you to hop in, then once you proceed to, that person drives away, parks and tells you to come in...then drives away in a repeated manner. :p

Deshan19, here is a non-regex one:

on @*:text:*:#:capscheck $1-
on @*:action:*:#:capscheck $1-
on @*:notice:*:#:capscheck $1-
alias -l capscheck {
  var %. ,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,%; $len($remove($1- [ %. ] )),%: $len($1-) - %;
  if ($nick !isop #) && ($calc(100*($len($removecs($1- [ %. ] ))-%;)/%:) > 50) && (%: > 5) { 
    set -e $+(%,c,$chr(32),$int($v1))
    inc $+(%,$nick) 
    if ($($+(%,$nick),2) > 2) {
      ban -ku600 # $nick 2 You've used $+(%c,%) of CAPS, and you were warned twice! 
      unset $($+(%,$nick),1)
    }
    elseif ($($+(%,$nick),2) = 2) { 
      .msg # You've used $+(%c,%) of CAPS, and this is your $ord($($+(%,$nick),2)) warning! 
    }
    else { 
      .msg # You've used $+(%c,%) of CAPS, and this is your first warning! 
    }
  }
}

It has two warnings before a kick/ban for 10 minutes. The percentage and ban time are fully adjustable.