It's just an extra bit of thread rod, a printed idler pulley, and some rubber bands and string. I have printed 10 parts since I put this on and have yet to recalibrate.
My software problems ended as soon as I switched to Skeinforge. Last night was the first time I trusted enough to let the printer run all night. I am now letting the printer run 24 /7 and my collection of parts is quickly growing. Here are some images of my most impressive print. The three objects that make up this part took a total of 8 hours to print. Its a bed corner, constraint bracket, and bearing insert for the Darwin.
Next on my agenda is to tackle my warping issue. Basically, the corners of the base of my print are pulling up, making the bottom not completely flat. It hasn't bothered me as of yet because all the parts I have printed are relatively small. I will eventually be wanting to print the X carriage, which is quite large. I am concerned that if I don't solve for warping before attempting this part that the part will be unusable.
I will be looking into different printing surfaces(right now I am using Plexiglas), cooling techniques, and printing speed to see if I can solve this.