Google App Engine is platform for building and hosting web applications on google web servers. During its preview release, only free accounts are offered. With this you get 500 MB of persistent storage and enough CPU and bandwidth for about 5 million page views a month (that's what Google says).
Probably in the future they will start charging if you want a best plan, but this plan should suit the most of you.
One of Google’s newly announces is that this service is going to support Java, so that's good for us the JAVA lovers
I think that i'll stop talking, and give you the link so you can start testing it and making your own thoughts. Google App Engine
Here are some of the restrictions:
* Developers have read-only access to the filesystem on App Engine.
* App Engine can only execute code called from an HTTP request.
* No support for task scheduling in the traditional sense.
* Users may upload arbitrary Python modules, provided they are pure-Python. C and Pyrex modules are not supported.
* Users are unable to download or run scripts on their database information
Fixed quotas
Quota Limit
Apps per Developer 10
Storage per App 500MB
Files per App 1,000
Size per File 1MB
Per-day usage quotas
Quota Limit
Emails per Day 2,000
Bandwidth In per Day 10,000 MB
Bandwidth Out per Day 10,000 MB
CPU Megacycles per Day 200,000,000
HTTP Requests per Day 650,000
Datastore API Calls per Day 2,500,000
URLFetch API Calls per Day 160,000
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OS:Windows Vista Ultimate Sp1
MD:Asus P5N-E
CPU:2.40GHz/Intel Quad Core Q6600
RAM:Corsair Dual Channel 4GB 800Mhz
VC:XFX GeForce 9800 GTX/512MB

