A list of my preferite Basic programs (and comments) is shown here.
Interpreter of this Basic language can be freely downloded at www.JustBasic.com. :-)
However with minor arrangements codes can be used in many Basic environments also.

+----------------------+------------------------------------------------------------------------------------+------+
| ASTRONOMY            |                                                                                    |      |
|    PlanetDist.bas    | Simply interplanetary distances (Sun, Earth and Pluto included) valid 1800-3000 AD | File |
+----------------------+------------------------------------------------------------------------------------+------+ 
| CHEMISTRY            |                                                                                    |      ! 
|    CaCO3-dec.bas     | CaCO3 thermal decomposition data, from NASA-CEA database (including p(CO2)equil.)  | File |
|    CaCO3-heat.bas    | CaCO3 thermal decomposition rate, from simple kinetic model (mole fractions)       | File |
+----------------------+------------------------------------------------------------------------------------+------+ 
| MATHEMATICS          |                                                                                    |      ! 
|    Bessel.bas        | Bessel data points interpolation (5 points)                                        | File |
|    Binary.bas        | Simple translation from decimal to binary format                                   | File |
|    Chebyshev.bas     | Interpolation using Chebyshev polinomials, with graphic output                     | File |
|    Cramer.bas        | Cramers rule to solve a linear 3 x 3 system                                        | File |
|    Cubic.bas         | Cubis (third degree) equation solver, including imaginary roots                    | File |
|    Lagrange.bas      | Lagrange interpolation of experimental (x,y) points with polinomials               | File |
|    Linear.bas        | Linear equations system solver. Uses triangular matrix. Simple routine             | File |
|    Linear-test.bas   | As above, benchmark for a linar system of 100 quations with 100 unknowns           | File |
+----------------------+------------------------------------------------------------------------------------+------+ 
| GAMES                |                                                                                    |      ! 
|    NIM.bas           | NIM game with essential graphics. Binary algorithm explained                       | File |
|    Magic_squares.bas | All possible permutations of magic squares 4 x 4. Text output                      | File |
+----------------------+------------------------------------------------------------------------------------+------+ 
| GRAPHICS             |                                                                                    |      ! 
|    Mondo.bas         | Graphics of the globe. bmp image cam be saved and used elsewhere                   | File |
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