Since you already have your answer, this is a great question for golfing! How about: 
perl -pe'eof||<>'

[download]

Update: Fixed bug found by BrowserUK. Thanks japhy!

Update: A few people have asked to see the original, buggy version. It was simply perl -pe'<>'.

In reply to Re: How to Print Every Other Line by sgifford
in thread How to Print Every Other Line by Neuroactive

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