MALM - A collection of UBASIC programs which can be used in number theoretic investigations. - http://www.riaca.win.tue.nl/archive/can/SystemsOverview/Special/NumberTheory/MALM.html
UBASIC Home - Downloads for version 8.8f, help files, bug reports, benchmarks, timings, and links. (Much in Japanese). - http://www.rkmath.rikkyo.ac.jp/~kida/ubasic.htm
UBASIC - Rather-old version (8.74) of this package. - http://archives.math.utk.edu/software/msdos/number.theory/ubasic/.html
UBASIC Programs - Simple examples for use in a Number Theory course. - http://www.unf.edu/~ramm/numbtheory.html