What Case to Use? Another modding question

Hi guys,
I'm thinking of rebuilding my Athlon 800 after it's motherboard blew a while back. I've got all the parts worked out, I just have no idea what to do for a case. I'm using the last of my monies to upgrade some systems so I'm on a £0 budget . I need some help to pick out what to do here so here are some options:

1- Powermac Cube Rip Off made out of Meccano (lets go back to our childhood)

2- Meccano ATX tower(back to childhood again )

3- An old MSI Micro ATX Case totally modded (Side panels and top panel will be perspex or whatever transparent material we have)


Now I have no more options. I was thinking of entering a modding competition. What do you guys think will be better given the fact I'll have a bit more money to play with if I make a meccano case