Good Finnish Disco is pretty hard to find, but well worth the effort. Just put these on the decks at a hipster disco at witness the smiles on everybody's faces - just to show them it's not too serious. Like a lot of our charttoppers up until eighties, lot of the good tunes are pretty much cover versions of international hits. Here's a few good examples, very Disko WTF-ish stuff.
Meiju Suvas' "Pommi oon" is simply quite wonderful. A decent bassline with some good horn action, but the real deal are the lyrics. You simply cannot resists to sing along with the lines (ruff translation) "I'm bomb, full of hot elemental force, you would have me, I'm a bomb, if you want to, you could extinguish". Very tacky, so much fun. It has a great singalong part too.
Karma - Raju yö
This one's the bomb. It's pretty straightforward version of Brother Johnsons' "the Stomp", but the real catch are the Finnish vocals. They're full of youth vernacular circa 1980, with references to going out to the city with the gang, to "ruff nites". It's so cool when sung in 80's Finnish, trust me. Risto has a cool edit of this, maybe we'll drop on an unsuspected crowd someday...
There's a good place to find more good, listenable Finnish oldies gems at here: Hiihtopipo & Kavallus-show. Just scroll down to suomispeciaalit I-IV. Big kudos to Hiihtopipo and Kavallus for those!