During the months of May and June Iceland goes through a period known as “Midnight Sun” where the sun does not set for 2 months. Although the further south on the island you go the less you’ll be able to notice the effects.
Icelandair is offering flights from Boston for around $400 and various other places that go through extended periods of long daylight (Sweden $471, Denmark $521, Norway $522). Prices go up considerably after June 15 so now is the time to go.
If you do happen to take Icelandair but not to Iceland, take advantage of their great Iceland stopovers. Spend a day or two in Reykjavik before your next destination.
Remember the best time to buy airplane tickets is Wednesday night and check your international faux pas before you take off!