I like its sleek and seemingly simple exterior with its sharp and soft edges, which when parted, reveal elegantly and efficiently engineered sophistication.
I voted MBA, even though it's rather heavier and bigger than I care for... but I do think it's striking. I agree about the iMac, though. I had mixed feelings about the aluminum design, initially, but it's really grown on me over time.
The iMac is the real head-turner for the average joe (if the reactions they get at work are anything to go by), but my personal vote would have to be the MBA.
current lineup aside, the coolest looking mac of all
time was the iMac G4. That was my favorite computer
I ever owned and it definitely made everyone notice!