pcu is a set of simple command-line utilities to expose the posix_fadvise and mincore syscalls. pcu-fadvise gives the kernel advice on the access pattern for files. This advice can affect all processes by all users accessing those files. pcu-mincore is used to determine which parts of a file are in cache. These utilties are targeted for Linux 2.6, but may work on other operating systems that support the mincore and posix_fadvise syscalls. mincore is not a part of POSIX, and posix_fadvise is uncommon despite being specified by POSIX.
pdf2htmlEX renders PDF files in HTML. It aims to provide an accurate rendering while being optimized for Web display. It is designed for scientific papers with complicated formulas and figures, so a precise rendering is the first concern, but general PDF files are also supported.
pdr (personal data recorder) and pdx (personal data expert) are applications that collect and evaluate mostly numeric personal data. The intended use case is for logging individual medical data (blood sugar, blood pressure, body temperature, weight, heart rate, and medications), but they can also be used for technical, sports, fitness, weather, environmental, or financial data. They work on a continuous flow of numbers in time that you want to monitor. Every data item can also be commented by text. pdr can use Twitter and email accounts for data input, which makes mobile phones usable for data input. It is one of the few free applications for diabetics.