Tallinn Reddit meetups? General Tallinning advice?

Hey there r/eesti,

Can anyone recommend good, quiet places with wifi to bunker down and study for an afternoon in or around Old Town Tallinn? (Good coffee and/or baked goods would be a decided plus).

Also, anyone perhaps able to advise as to how open the University of Tallinn is to visitors using its library facilities?

Otherwise, are Reddit meetups much of a thing in Tallinn? Do you guys do that? I've been to some in Berlin, and they are pretty fantastic. I'm an American heading down to Estonia via Germany and Finland, in case that's at all relevant. I'm a 20-something musician type/professional student/freelancer. Yep. One of those. Anyway, if anyone is keen to grab a drink somewhere (Wednesday, 22.4, perhaps?) I'd certainly enjoy meeting some locals/expats/anyone feeling up to socializing for the evening.

Oh! And does anyone have experience by chance with Saunalahti (Finnish) sim cards in Tallinn? In terms of functionality on Estonian partner networks that is.

Tl;dr Travelling to Tallinn this week. Cafes with wifi? Using University of Tallinn facilities as a visitor for the day? Reddit meetups? Finnish sim card functionality in Estonia? Cheers.