Let me be the first to recommend the Panaracer Pasela, which is available in 27x1-1/4" and 27x1-1/8" sizes, both in their regular version and the more puncture resistant "Tourguard" variety. I've only ridden the Tourguards, in both 27x1-1/4" and 700c x 28 mm (roughly 1-1/8" in width) and I like them quite a bit. Schwalbe also makes some pretty highly regarded 27" tires.