I ride Bell Sports Streetster folding tires in 27" and like them. They're also available throughout the USA at Walmart stores in 650A/26x1 3/8. Also investigate: Michelin Transworld City, Specialized Tri Sport, Vittoria Randonneur, Vredestein Girando.
HTH,
TCS
I also bought a pair of these as a cheap experiment and I really like them.
They were supposed to go on my Sprite but I have been happy with them on my touring bike so I guess they will stay there for now.