GSoC 2015 project with PostgreSQL

Dear Developers!

My name is Pedro. I am a Master's student from Germany and am interested in
doing a project with PostgreSQL as part of the Google Summer of Code.
I am studying IT-Systems Engineering at the Hasso-Plattner-Institute in
Potsdam where most of my studies is about in-memory databases and general
data science topics.
Recently I have developed a SQL parser for the research database Hyrise (
https://github.com/hyrise/hyrise) where I also found some inspiration in
the SQL parser of PostgeSQL.

On a first look most of the ideas mentioned in your wiki seem to be fine
for me to take on, but I am unsure of how to write those into a project
proposal since I don't know exactly what priority and complexity each of
these have at the moment.
It would be great if you could give me some insights on what you think
would be a great contribution to PostgreSQL in the scope of GSoC.

Also, I wrote my Bachelor's Thesis on bit-packed vectors of dictionary
compressed data. Using such a data structure might be something I could
investigate. What do you think?

Thanks and Best Regards!
Pedro