This is probably my favourite layout. It provides a great deal of workspace. You can use hutches on different sections for additional storage. It can be used in small or large rooms.
Another nice feature is that two people can quite easily share this space and not get in the way of each other.
You can create the basic U-shape with one desk and tables or islands to the sides or there are U-shaped units available from some office furniture stores.
Creating the U-shape with the penninsula, will take a little more work since it does involve more space but if your future plans include having more computers this is quite possibly your best bet.
This layout also works well in shared rooms, it makes the most of space and room for storage without spreading into the other space.