The Great Guild Hall (1410) is a wonderfully complete testament to the power of Tallinn's medieval trade guilds. Now a branch of the Estonian History Museum, its showpiece exhibition is 'Spirit of Survival: 11,000 Years of Estonian History', illustrating the history and psyche of Estonia through interactive and unusual displays. There's also the old excise chamber, with numismatic relics stretching back to Viking times; the basement, exploring the history of the Guild itself; and sections on Estonian music, language and geography.
The major exhibition poses such questions as ‘Is Estonia the most secular country in the world?’ and ‘Have Estonians been happy in their own land?’ (The answer to the latter is 'no', apparently – statistics suggest they’re one of the least happy peoples in Europe.)