WOW Air via Expedia have roundtrip airfares travelling from Boston (BOS) to Iceland (KEF) for $230 including taxes and fees. This is nonstop service.
Departs BOS: April 10, 11, 24, 27, 28, 29, 30
Retruns BOS: May 4, 5, 6, 11, 15, 16, 17, 18, 20, 25
Use dates above and book it on Expedia.com .
Sample travel itinerary attached