Mike,
Just about the time that Lionel was starting to design a modular "standard" I decided to develop a plan for a set of modules our club could use. I had just read Jim Policastro's article in OGR about the "second generation" of their club's modular layout. He made a point to say that most people like to see trains running so they didn't do a lot of sidings or switching. That made lots of sense to me!
My modules came out with some similarities to the Lionel plans, but some things are different. The similarities are purely coincidental, the differences are a result of a different view of "the big picture".
My modules are based on smaller track curves - the inside is O36, the outside is O48. My corners are significantly smaller, 30" x 30", and each corner is one piece. The Lionel module has two-piece corners and larger curves at the corner.
My modules use 30" x 30" corner modules and 30" x 60" straight modules. Those dimensions made more sense to me, and at 5' long still fit in almost any car. My small SUV can easily carry 4 corners and 4 straights, plus the accessories, trains and transformers.
Here are a few diagrams:
... configured as a 5' x 10' layout, 4 corners 2 straights.
...configured as a square layout, 4 corners 4 straights
Both the Lionel version and mine use Fastrack, with the first track 3.5" in from the front edge, and the second track 9.5" in from the edge (again, purely by coincidence - maybe we both figured out these dimensions work well with corners.)
Our club tried out modular layout (5' x 10') out at a local train show, and it was well received. My design uses no legs, and sits on 2 folding tables strategically placed at the joints.
My modular layout is all felt topped (coincidental with my lack of skill as a scenery artist), and each 5' straight section portrays one scene, ie. downtown with stores, suburbs with houses, farm, airport, etc.
I found some pics from our first event. A 5' x 10' layout isn't a huge layout, but took a while to develop. Lights for buildings and stores are mounted on the boards, but the buildings are not. They are placed on the modules after they are attached together. It took us about an hour and a half to carry in the modules and set up, less than an hour to break down (3 guys).
I would suggest that you start with a few modules... there's always room for more!
Ed
Two loops for trains plus a puhbutton-operated trolley and a pushbutton-operated aquarium car on one end and a pushbutton-operated helicopter car on the other.