AppFog is astonishing. Deployment take less than one minute. Configuration is super-fast and easy to do. You got 2GB of RAM for free up to 10 applications free forever! So your hosting don't cost you a dollar.
One thing that you really need is the .htaccess to move the directory to /web where you have your index.php
You can see the example application code on mine github public repo: https://github.com/emgiezet/iTVPDownloader
I got an example application that I created in less than 3 hours. With working code and app created on the AppFog.
Deploy looks like this:
cd your/app/dir af login af update yourAPPname
Less than one minute and your code is there and working. For the performance I've added the second instance of mine application. Requires only the app restart and its there. Two clicks and ready. As stunning as easy.
I got the lot's of traffic due to polish digg.com like site (wykop.pl). And they cannot kill the performance of the app.
Try it live at: http://itvpdownloader.mmx3.pl/ it works like charm.
Add Redis caching (super easy to configure)
Add MySQL(doctrine driven) database with some stats.
All of that without adding a dollar to the project.
Is there something more awesome to prototype your PHP startups?