Reading is my guaranteed way of escaping boredom and a time killer. So, when I am on the road I often look for a chill place with bookshelves and a working air conditioner.
There are several public places like this in Tallinn where I pass my reading sessions, when I am stuck or just in need to kill some time. One of them is 4th floor of Viru Centre, another one is on Pärnu mnt Rahva Raamat, but my favourite one is on the second floor of the Solaris Center, Apollo bookstore. First of all, they have plenty of books, albums, maps etc. Secondly, I like their jazzy-ambient background music selection, and thirdly, they have plenty of comfortable armchairs and hanging baskets.
This shop also has plenty of stuff in English and some other languages. On a rainy day in Tallinn you can hide here, find a comfortable chair and enjoy your time with one eye on the book, and another one on people passing by. It can be entertaining for some time. You may play table games with your mates here as well. And, of course, all those good things are totally free of charge.