Somewhere between a sock and an actual bank lies the Executive Safe-T bed. Hollandia International's design incorporates a heavy-duty safe underneath the mattress and a cover in the head joint of the bed base.
The bed was originally developed for a wealthy international customer that wanted to keep a handgun close by at all times, but it is just as useful for keeping you valuables secure. The safe can be added to any Hollandia bed for around $400, but the beds themselves can run in excess of $20,000. As an alternative, you could always pick up a pair of skid marked security briefs for around $6. It's probably just as effective. [Hollandia via Born Rich]