I blogged "Extermiknit!", a knittable Dalek, back in 2007, but it turns out that an even cooler knittable Dalek of the same name was created on Feather and Fan in 2010, with an opening hatch containing a Kaled mutant, and here it is.
After completing the top of the Dalek as specified, I created an opening in the front by steeking carefully along the vertical line between the knit “instrument panel” and the purled rest of the midsection–just used some sewing shears and cut straight through the middle of the rightmost line of knit stitches, along the entire height of the midsection. I then carefully unraveled the stitches from right to left on the rows above and below the desired door area, to the left end of the “instrument panel”, and placed these two horizontal pairs of exposed stitches on DPNs.
This creates a kind of door flap, hinged vertically along the left-hand side. I sewed down the outer edge of the door with one yarn tail, and used a sewn bindoff and the other two yarn tails to fasten the top and bottom of the door flap. The door flap was now bound off and would not unravel.