I agree with writing actual applications to hone your new knowledge. My first real applications in java were a calculator and a CD collection application. I wrote these without an WYSIWYG IDE. It helps to really see how things work if you don't use a GUI "builder". If you want to get ideas for good projects you can read "Java Cookbook" published by O'Reilly. It provides some programming example projects that can be expanded upon. Finally, read a good algorithms book (can't think of any examples, sorry). Java is great for supplying many objects that hide the implementation, but it's still helpful to know the theory behind these implementations.

Right. In the U.S., fingerprints are kept indefinitely. At least in the local law enforcement offices. But they are viewable/searchable by other agencies as well. The reason they keep these is for identification purposes other than crimes such as after death or missing person, etc. I'm sure DNA will be kept for the same reasons.

Let's say the hardware DOES cost $150. I think over the lifetime of the hardware they can more than recoup the cost. I think it's in the realm of possibility to get $10 add revenue per month per user. That includes search revenue and adds splashed all over everything. They get their money back after 15 months. Let's say the average lifetime of the hardware is 2 years, they make money after a while. Of course, they make money sooner as the hardware gets cheaper.

Yes, deprecation of MySQL is my fear. It seems to me that not keeping some form of MySQL free is like biting the hand that feeds it. There is plenty of cash flow in the form of services that can be had. I'm hoping that if Oracle cannot support MySQL development/maintenance, it will be spun off into a separate business arm ala RedHat/Fedora. BTW, there already is a fork of MySQL, Drizzle (http://drizzle.org)