[XCSSA] Power Supplies Continued

[X-otic Computer Systems of San Antonio]

Alright I've got another couple of questions about power supplies :)  
While I am likely going to make things easier on myself and buy a pre- 
made mainboard and parts kit for my MidiBox SID, I still need to  
figure out how to power the thing. Fredrick was kind enough to let me  
have an extra C64 PSU, but I'm actually thinking it might be fun to  
make my own power brick.

The idea is to have 1 or 2 transformers (I'm having trouble finding  
multi-taps that output 9 and 5VAC) connected to mains and then rectify  
and regulate those. My previous method called for using voltage  
regulators in series with a big heatsink. That works, but it seems  
kinda lame and intentionally less efficient.

So, my questions are then - for fusing the 120VAC input, do I just  
need to fuse the positive line (and not the neutral)? And, assuming I  
use a 3-pronged cord, do I ground everything to the 3rd prong  
(basically connect it to the ground plane of the board, assuming I get  
a printed board)? Also does anyone know what those laptop style cable  
and connectors are called? You know, the ones that has a standard 3- 
prong on one and hexagonal female on the other? It looks sort of like  
a nuclear warning sign. Dell uses it alot on their connectors. I  
figured that would be easier to use than trying to strip a normal AC  
table and all that stuff.

If anyone wants to see my (very much alpha) design, I'd be happy to  
send it your way!

Thanks! Oh and Happy New Year!

Tim