I still don't see how the $400 pays off. If you buy the books used on half.com and then sell them back on half.com, with an average loss of...

The Kindle ROI is only going to come from convenience and portability. It's not going to come from book savings.

Computer books tend to be either obsoleted or replaced by...

I would definitely push this way down in a wrapper, so the app was a shielded as possible from the raw EAV. Less room for developers to make mistakes...

Since you are dealing with internationalization already, what form are you using for numeric data in the fields?:

9,999.99

9.999,99

Your C# code will need to parse with a specific locale, otherwise users...

EAV has its place. Regarding performance, indexes and efficient code can usually mitigate that.

I'd like to see more discussion about type-safety and whether there are any tricks for that...