Hasin Hayder has put together a list of cloud hosting providers that are already set and ready to go for PHP applications. His list highlights a few of the free ones.
I will be focusing on some of these free cloud hosting options available out there. One thing to note before you proceed - these free cloud hosting options are very good to develop and test your applications (in dev+staging environment) and it may not be wise to deploy the production version of your application with any free plan (Except Amazon AWS's free tier, its production ready).
He has four different services on his list, ranging anywhere from small to industrial strength, depending on your needs:
- Amazon's AWS
- PHPCloud (from Zend)
- Heroku (traditionally Ruby, now supports PHP too)