After vcoleiro1 fantastic Small space invaders machine (Check it out
http://forum.arcadecontrols.com/index.php?topic=112891.0)
I thought about other ways to make a small machine then thought of other ideas about arcade or games in general so i'm going to throw them out and see what everyone things
First off was a mini pinball like hand sized for the desk now i came across a fantastic android app called vector pinball
I thought an old android phone could be used and a overlay created to sit ontop and a small desktop pinball machine is made
Here is what vector pinball looks like (Looks way better on a phone)

I think that with a graphic printed onto clear sheet and put ontop would work great and vector pinball author is happy for new tables to be made

My other idea was something i've always thought of but never implemented as i couldn't find a good enough use for it.
A roof mounted projector pointing to the ground or a table
I did a small mockup holding a spare pico projector i had and a controller


Now cause it's a topdown game it's perfect for this and 4 people can play around the table cause they don't have to see it from the same angle as you do in an arcade machine.
It's like a virtual scaletrix track
I also thought of Why not have the projector project on the ground and you have an instant mini golf/putt putt course
Now this is harder cause i would expect using a real putter and a camera that sees the club head and determines the speed when the club reaches the golf ball being projected.
I don't think there are any wii games that do top down putt putt but if there were i could easily do a demo and see how well it actually works.
Anyway in a game room this virtual putt putt would be a great idea you have multiple course but only use a fraction of the space which isn't taken up by a machine.
I did use the pico projector on a pool table and a camera track movement and ripples where shown on the table top but of course a pico projector isn't bright enough and doesn't have the biggest image either
That's just a few ideas does anyone else have any or have other adaptations to the ones i've mentioned?