Gross :(

Argyroneta aquatica, aka Diving bell spider/Water spider.

Quality of the photo really sucks because I did not want to put my hands too close to that creature. :( This truly is the biggest spider I have ever seen in Finnish nature. *Shivering*

(The hand next to it is my son's hand, definitely not mine!)

At first I couldn't even believe it's real because it was so shockingly big. :O