Unenthusiastic about spending thousands of dollars on electrophysiology software like pCLAMP? Try the free and open source Strathclyde Electrophysiology Software. It’s a suite of programs for recording and analyzing signals from intracellular electrophysiology experiments. It’s for Windows. Many standard DAQs work right out of the box. Encouragingly, it has been updated routinely since 1997, including as recently as Jan 16, 2013.
The MATLAB-based Ephus, from the Svoboda lab, is another option. There are others as well (here’s a list), but these are the two open source, free options that seem to be regularly updated. Let me know if there are others.