Link list for today

1. Mighty Mouse 徹底清潔教學-分解篇
2. XenServer is now free (from Slashdot). (Almost plan to install a XenServer Express today...)
3. PyBrain - machine learning library for python?!
4. Google App Engine can buy quotas now, finally. Reduced free qoutas in May: 10GB in-and-out to 1GB, 46 CPU-hrs per day to 1 CPU-hrs per day, but fixed quotas for applications with billing enabled will not be affected.