Durable design. We like the styling of the Locker Tall Loft Bed from PB Teen. Unlike many traditional bunkbeds we've seen, the base of the Loft Bed offers more space and allows a variety of different configurations.
Depending on your needs, you can have a double bed below and enough room for underbed storage as well.
We also this configuration of a the coordinating desk creating a large workspace under the lofted bed. The twin Loft Bed is $999 here. The prices of the coordinating pieces vary.