here we go, the best script on IRC! I garantee it is superb usefull!

alias uslap {
  var %usweight = $r(70,100)
  var %usepm = $calc(%usweight * 9.8)
  var %ushp = $r(5,150)
  var %usjk = $calc((%ushp * 142000)) / %usepm)
  ;142000 joule per kg 
  describe $chan sets up $1 with $bytes( %ushp , b) kg of hydrogen and sets it off.Considering $1 weighs about %usweight kg, Making $1 shoot up into the athmosphere for $bytes( %usjk , b) meter
}