Favorite thing: The thing, that I have seen almost from first moment when I entered Tallinn's old town was nicely decorated and colorful doors. Almost in every street it is possible to see such doors with different wooden carvings and intensive colors. It could be possible to make a photo gallery just of old town doors.
Favorite thing: If you have an eye for detail there will be much to charm you in Tallinn. Everywhere you go there are little things to catch your eye - fabulous old doors and door knockers, glimpses of quiet courtyards through archways, painted gargoyles and carved water spouts, a lovely painted mediaeval clock on a church wall, light and warmth spilling out of windows on a snowy night, painted signs, a royal baker's shop marked by a crown-topped pretzel, - all this and much more. Keep your eyes open as you wander through the narrow streets, look up as well as around you.
While visiting the Dominican Monastery, we came across a posting that explained the origins of the "ettics" stones, which stand out yp to a foot on each side of house entrances.
Basically, the ettics were used instead of addresses by house owners: each had a different design and was specific to its house. Increasing street traffic in the 19th century led to the removal of many of these stones, but you can still see some scattered around the Old Town. (The famous "House of the Blackheads" door still has its ettics.)
Once we learned about these stones, we started looking for them while strolling in the Old Town. It made our walks even more interesting!
(By the way, Tallinn is the only place where I ever found/heard the word "ettics" used. If anyone knows another name for these stones, I would be glad to hear it.)