My honours project - databases using dynamically attached entity-properties

Hi,

Was wondering if people would mind having a read over what I plan to do for my
undergraduate honours project - you can get the proposal here:

http://www.mcs.vuw.ac.nz/~eddie/489_Proposal.pdf

What I'd basically like to know is
a) Is this problem worth solving?
b) Is there already a good solution (particularly, within PostgreSQL)?
c) Any other feedback or comments you may have.

Regards
Eddie Stanley