Except scientific (non public) projects I also have some general interest projects:
PocketMK is small program for PocketPC which simulate famous Russian calculators MK-61 and slightly extend it.
UDAV is front-end for MGL scripts. It has windows interface for data viewing, changing and plotting. Also it can execute MGL scripts, setup and rotating graphics and so on.
Also I recommend to look at:
EngLab is a cross-compile mathematical platform with a C like syntax intended to be used both by engineers and users with small programming knowledge. It is extremely scalable and allows users and the community to easily compile their own functions as shared objects.
3Depict is software for analysis of scientific datasets commonly encountered in atom probe tomography. You can manipulate, interact with and analyse point based datasets.
GnuWin provides ports of tools with a GNU or similar open source license, to modern MS-Windows.
LLoL is project collecting, organising, classifying, and maintaining important URLs about Linux and the Open Source movement for all levels of Linux users. The LoLL project now has 4000+ links which are updated usually on a daily basis.