How do I promote my Windows based free SMS application without spending any money?

Thanks for the suggestions. Unfortunately Freshmeat doesn't want applications that only run under Windows and Sourceforge wants only open source applications which puts mine firmly out of the running (it's free, just not open to all). I have to admit it took me a long while to get the post just right so that (hopefully) people didn't complain :)

still, set up a page and tell all your windows+SMS:ing pals about it, if they like it, they'll tell others. Then wait.

http://www.tucows.com?

I wrote a fun online game once. In order to get it spread around, I gave my friends a challenge: If it was played a million times in a month, I'd throw a pizza and beer party for them. It worked like gangbusters. I should have told them not to be spammy assholes about it (even though they weren't, they could have been, which would have been bad). They ended up posting things on a few forums they were active in, mentioned it to their friends who linked to it in a couple places, and it started spreading from there by word-of-mouth. I think it took 2 or 3 months to get a million plays, so I didn't even have to pay out.

There's a http://www.versiontracker.com/windows/ version for Windows that might work. I don't think it is as popular as the Mac version which is like a must-visit site for applications. Also make sure you optimize your website to make sure it will be high in the listings. That part is free.

make reference to it on Ask Metafilter, and hope it catches on that way.

You're trying to reach the people who actually use SMS, so look for message boards relating to high end cell phones. Places like http://www.allaboutsymbian.com/forum/ and http://www.howardforums.com.

If it's any good, the word *will* get out there. To start the process, make contact with other developers who will have been through this process before; if they like it they'll be keen to put the work of a fellow developer out there. Put a brief but appetizing link to the software in your signature, business card, and when meeting people – it's all about small networks, not mass advertising. Lastly, good luck and be prepared to wait a while after you sow your seeds. Plutor, that's a marvellous idea!

If it's genuinely good, try a post in uk.telecom.mobile They're largely a friendly bunch, and there are occasional posts in there asking for a good sms app. Where is it, anyway? I tried the site in your profile, which shows me that I've used a couple of your perl scripts, but nothing about this.