Oslo, Stockholm and Copenhagen aren't usually considered budget destinations, and fares are typically on the high side. SAS has announced a pretty good sale for spring 2010 travel, however, and it's worth a look (we say "pretty good" because we're comparing it to some of the fares we've seen to Stockholm from Newark when Malaysian flew the route for fares in the $300's with tax).

Anyway, this sale is for travel late March to mid May, with tax-included fares from Newark starting at $619 round-trip. Also of note are summer business class fares at rather amazing prices.

A Saturday night stay is required, and you can stay up to 12 months. Change fee is a whopping $300, so beware.