Alternative to Email Piping

I am developing a webapp that lets you update your account by sending a simple text email, then it sends a simple email back confirming it. This was working fine at my previ开发者_运维百科ous host, who had cPanel with email piping.

Since then, I've moved to dreamhost, particularly because lifehacker rated it #1 and gave an incredible discount. I've found them great so far. But then when I tried to transfer over the email piping feature they told me they do not support email piping. The only thing they support is Forwarding mail to a shell account which requires you to upgrade to a VPS anyway.

So what alternatives do I have? The only thing I can think of is having a cronjob executed every 5 seconds that checks an email account via POP/IMAP, but (1) that sounds quite intensive on the server to have that running every 5 seconds, and (2) from the sounds of that wiki article and what support has told me, I think that is what requires a VPS account anyway...

Help!

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Here's another option, a service that consumes email and posts to a form of your choosing:

http://blog.webhooks.org/2009/02/13/restful-email-over-http/

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The only thing I can think of is having a cronjob executed every 5 seconds

Cron jobs can't be processed more than once a minute, and doing this once a minute doesn't sound two horrible, assuming that you aren't doing any intensive processing when importing the email.

If you're stuck on shared hosting, then this is probably as good as it's going to get.