What we found was a Med cruise (Amsterdam to Rome) aboard Holland America's Prinsendam. Though we're still flying to and from Europe, the ports and ship (Prinsendam is tiny and intimate) make it worth the hassle.
During that search, we came across another we already booked for March. It runs 13 days from New York to the Panama Canal and back, aboard Cunard's Queen Mary 2, an old friend from our London/Transatlantic trip in '04.
If you feel like joining us on either, email me and I'll give you booking details and hook you up with our travel agent (who's just opened her own office).