That's 33, not 24 (since omitting the first line gives a compile error).

If you want really small, try 4!

do f
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I'm sure f can be made way smaller than ruby.

Update: Downsized from 10

I meant the following :)

ruby -e 'x=i=1;p x+=i=x-i while+1'
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get it? :)
It is Ruby and not Perl pro lang.
Never-the-less ++

While your first post ran in Perl, this one doesn't.

syntax error at 584097.pl line 1, near "ruby -e "
Execution of 584097.pl aborted due to compilation errors.
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Meh, if you don't have to use perl, you can do much better: Re: Fibonacci numbers (again).

Update: let's put them under each other to see which one is longer.

         1         2         3
123456789012345678901234567890123
dc -e1d[pdsd+ldrlxx]dsxx
ruby -e'x=i=1;p x+=i=x-i while+1'
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It's also easy to shorten the ruby version by two characters

x=i=1;loop{p x+=i=x-i}
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