We can even setup a blockchain-like online wallet service using coinpunk code. But I don't know whether running a service like this is legal or not (considering lotto.).

As the GUI is delayed, I'm interested in a GUI made in pure js.
The benefit:
1. quick
The html+css+js makes it very easy and quick to write GUI. I think I can make a very simple prototype in a week if I can have some spare time as long as JSON-RPC interface is ready.
2. cross platform
Even on mobile platform like ios and android.
3. responsive page design
This makes it look and feel well on different devices.
4. easy
JS is easier than C in my opinion.