I've been working on a new Papilio board - code name Papilio Flex. Papilio Flex is meant to address the following things: There is a lot of confusion about which FPGA board a new comer should purchase. The Papilio Pro with SDRAM or the Papilio DUO with SRAM? I want to clear up this confusion and make a single base board that can be expanded to be exactly what you need. Then the choice is between Arduino footprint and GadgetBox footprint instead of technical features. We need a low cost option without USB or external RAM for for small IoT projects.  We need to allow a high speed USB interface. We need to allow people to swap out SRAM or SDRAM or DDR memory depending on what is best for their application. The features of this new Papilio Flex board: There is a bare minimum on the base board. Just Spartan 6 FPGA (in the cheapest footprint), switching power supply, and two PCI express connectors.  One PCI express connector is to add a USB addon and the other is for a memory addon. The entire board uses the Universal eCog Scheme to allow a GadgetBox enclosure and eCog peripherals to be used with the FPGA board. Here are the design files: https://github.com/GadgetFactory/GadgetBox-Hardware/tree/master/hardware/GadgetBox-Papilio-Flex Would love to hear people's ideas and feedback.