There comes a time when every procrastinator needs to take a moment to look ahead. Or at least look a teensy bit ahead. Norwegian is having a fall fare sale for flights in September through November, making it a good time to stop saying "someday."
The flights are primarily out of Boston and New York, but there are also deals flying out of San Francisco and Los Angeles. The airline is advertising $99 one-way tickets in the sale. For the most part, you aren't getting departure and return fares that low, but the prices are still well below average.
Flying out of Boston you can get to Bergen, Norway for $203 round trip; Shannon, Ireland for $234; Dublin, Ireland for $245; Copenhagen, Denmark for $267; Belfast, Ireland for $277; and Edinburgh, Scotland for $326. Departing from New York, you can get round-trip fare to Dublin for $255, Belfast for $278, Edinburgh for $328, London for $405, and Paris for $419.