QMentat helps you practice mental arithmetic. It uses arbitrary-length fixed point arithmetic, and can handle any size numbers, only limited by the size of your screen (and in the case of division with an integer result, the speed at which the number can be factored). It is also quite configurable, allowing you to tailor the questions to your needs.
Shelk-test is a program for creating tests for students. Tests take up just three modules: creation, testing, and reporting. Shelk-test can insert images into all types of questions, making it possible to create a question such as "What is shown in the picture?" All tests are stored centrally in a SQLite database, increasing reliability and allowing you to have a database file without having to install a database server.
AbulEdu Calcul Mental is a software tool that trains children in mental calculation as stipulated by the French Ministry of Education for primary schools. Activities include addition, subtraction, multiplication of integers, addition tables (+2 to +9), times tables (x2 to x9), additional additives (to 10, to 100, to 1000), multiples (of 5, 10, 15, 20, 25 and 50), and orders of magnitude (with additions, subtractions, and multiplications). There is also an editor and selective launcher.