Sony has announced a trio of new Walkman portable media players that start at an already absurd $1,899.99 for the NW-ZX900 and climb all the way up to $5,899 for the gold-plated NW-WM1ZM3. Sandwiched in between is the $2,999.99 Walkman NW-WM1AM3, which is nearly identical to the WM1ZM3, just minus t