I have been interested in trams ever since I used to travel on one to school in Aberdeen in Scotland. I have collected a lot of information about the Aberdeen tram system, from a variety of sources (some rather obscure now!) which I gratefully acknowledge. I didn't take a decent photograph then, and it's too late now! Instead, here's one from James Hamilton, showing a tram at the terminus of the reserved track at the Sea Beach: my thanks to him.
In the town of Gmunden on Trauensee in Austria, there is a tram service which runs from the railway station down to the lakeside.
Mail was carried on many tram systems, and I collect material which shows this by a special cancel or cachet. Here are some envelopes and postcards which bear cancellation marks from the Hamburg (north Germany) system, which operated from 1920 till 1953.
Huddersfield had post boxes on its trams for many years. Here is my (unfinished) thesis on the development of The Tram Post of Huddersfield, with extracts from the minutes of the Town Council and the Post Office.
A good site for keeping in touch with the development (resurrection?) of the tram in today's cities is the Light Rail Transit Association.
Brussels has some good-looking trams..
The Innsbruck area has a long history, including the city itself, the Igls line and also the Stubaitalbahn - and the Lokalbahnenmuseum for North and South Tirol.
Salzburg has the light railway to Lamprechtshausen (and some trolley buses).
Vienna has city trams, a Tram Museum, and the Badnerbahn.
Llandudno's Great Orme is an interesting contrast in these 1987 photos.
Australia and New Zealand offer many varities of trams - and sunshine too!