roundtrip first class ticket on Delta booked with Korean Air: 45,000 miles (Delta charges 22,500 each way or 45,000 roundtrip in economy, so this is a great deal!) (themilesgenie.com)
For example, one very popular sweet spot is using 120,000 Virgin Atlantic miles for a roundtrip first class ticket to Japan with ANA and only about $ 180 in fees. (uponarriving.com)
Getting a roundtrip first class ticket to the Middle East or Africa for less than 176,500 miles (Thanks Raj) and $ 404 is not too shabby, methinks. (lazytravelers.net)