FPS

update=function() if system.time()>=t then t=system.time()+1000 s=f f=0 end end
draw=function() screen.clear() screen.drawText(s+" FPS",0,0,50,999) f+=1 end

Something one can count on ;)

Alternatively, you can just print out system.fps. :)

screen.drawText(system.fps +" FPS", 0, 0, 50, 999)

(I found out about it yesterday. I was using my own fps counter as well.)