Drinking from saucer

Certainly it's an old tradition in Sweden. You pour the coffee from your cup into the saucer and sip it - usually quite noisily - after blowing a little on it (to cool it). Dricka på fat (drink from a plate, i.e. saucer) can be combined with dricka på bit (drink with a lump, i.e. lump of sugar). You take the lump of sugar between your teeth and sip your coffee (from the saucer) through the sugar. Neither of these customs are, however, common in polite society... And, generally speaking, I've only ever seen older people do it, years ago, and in the countryside. Today's urban and international Swedes are more likely to have a latte - without sugar - in a tall glass, no saucer.

Well, you shouldn't do this in public - it's impolite. You could do it alone in the privacy of your house though. @hoc_age got this part right:

In fact, it seems that people would drink both from the cup and from the saucer: After being served a hot beverage (e.g., coffee or tea) in a cup on top of a saucer, some would pour a small amount of the beverage onto the saucer, and then drink from the saucer. There's evidence that this was reasonably common into the 20th century, and evidence that some still do, for a variety of possible reasons!