PPower4 is a programm to build PowerPoint like presentations from LaTeX. LateX source can be compiled to PDF and PPower4 adds some special commands to your LateX. You e.g. set a \pause command whereever you want and the presentation will stop there an wait for a key stroke, just like PowerPoint. PPower4 is a fantastic java postprocessor an can be found at http://www-sp.iti.informatik.tu-darmstadt.de/software/ppower4/