Micromachining techniques such as focused ion beam milling have become an integral part of the design debug cycle at many companies for providing fast verification of bug fixes in silicon. With hip chip packaging becoming more prevalent for future high performance processors, it is necessary to perform circuit edits and bug fixes on the silicon while the chip is packaged in the hip chip package. With this technology, however, conventional frontside probing and traditional circuit rewiring of packaged devices are not practical. We have developed a combination of new micromachining techniques for directly accessing metal signals from the backside of the chip. Here we will describe this new process, the technologies used, and some basic applications.