Comment by waterhouse

Just for the record, let's count to 100 million. And add the numbers up while we're at it.

  ~ $ time (echo '(do (= n 0) (for i 1 100000000 (++ n i)) prn.n (quit))' | arc)
  Welcome to Racket v5.3.5.1.
  Use (quit) to quit, (tl) to return here after an interrupt.
  arc> 5000000050000000
  
  real	0m28.561s
  user	0m28.308s
  sys	0m0.249s
  ----
  ~ $ time (echo -e 'n=0 \ni=0 \nwhile (i <= 100000000): \n  n += i \n  i += 1 \n\nprint(n)\n' | python3.3)
  5000000050000000

  real	0m30.244s
  user	0m30.230s
  sys	0m0.013s

It would appear to be competitive with Python on my machine on this particular task. (Also you can make it faster by dropping into Racket.)