http://en.wikipedia.org/wiki/Model_railroad_scales

Bear in mind, smaller scales can be much more expensive.

Z scale trains are manufactured by Marklin, Germany and all models are of German prototypes.

The scale is 1 : 220.

A single storey bungalow, with hipped roof, is about 5.5 m high (18 feet) so in model form 5.5 m = 5500 mm divide by 220 = 25 mm high or 1 inch high.

Architectural models, used for illustrating developments use a 1 : 200 scale. As houses can vary in size the difference between 1 : 200 and 1 : 220 would not be noticed. These architectural models are just plain outline shape so door and window representation would need to be added.

I have found items to match Z scale in Easter eggs, and on keyring chains, holiday souvenirs and novelty items.

60 foot containers are 83 mm in model form in Z scale. Typical double boggie oil tank wagon is 63 mm, four wheel oil tank 30 mm and typical passenger coach 85 mm.

I also have the T scale mentioned by Geof, and while fascinating the are nearly too small to give the feeling of the mass of a train.

Seán from Éire

You may be interested in hearing about a new addition to the ‘smallest scale train’ that is called T scale from Japan. It is only 1:450 scale. By dividing any known measurement by 450 will produce a scale measurement such as 10 feet would be only 1/4 inch in this scale as an example.

Although somewhat limited in what it currently has to offer, it is commercially available. From what I have read, the track itself is magnetic to keep the train from derailing. It can actually operate upside down because of this! Here is a link to check it out:

http://www.youtube.com/watch?v=NXSmyJr5qfI

Cut & paste the link into your browser to take a look.

Hope this helps.

Geof from the US