SL-6000 15" Laptop Bag - £9.99 delivered @ Play.com !!
Looks like a bargain to me. Also for most of 16" ones according to description.
Description : An elegant Notebook Bag for 15" and most of 16" Notebooks! Made of robust nylon material, this bag protects your Notebook against damages and dirt. The main compartment is extra strongly padded. An additional front compartment offers space for handys, CDs, visiting cards, etc. A rubberised bottom offers a secure stand on every surface. Both straps can be tied together through the velcro fastener.