McSimAPN : is a personally developed simulation tool, for modelling any sort of dynamic system. It incorporates both discrete event systems , by using a PetriNet formulation and Continuous (analog) systems by simple numerical integration.
The two modalities function together in a block diagram form of model. It isn't as pretty nor as powerful as SIMULINK but there's a lot less to learn (and to pay for).
It is designed for easy interactive use on personal computers. The user can run the process, plant or system, make changes on the fly, see magnitudes change as the run progresses, stop and save conditions to come back and try again.
Microsoft Excel Spreadsheets with VBA macros can be linked in (OLE) giving the user the ability to provide any programmable functionality interacting with the existing range of components.
You are welcome to download the software and try it. If you need help then contact me.

Algol: Brief exposure in an academic environment in the 1960's.

Analogue Computers: As an electronics engineer and as a university professor, I was very familiar both with the internals of analogue (analog) computers and their application to industrial and aerospace problems. The experience goes back to the days when analogue computers had +/- 100 Volt reference supplies and 300 Volt power supplies for the valves (tubes)! It also extended into a lot of experience with "digital analog simulators" (DAS, CIDAS, MIDAS) and continuous simulation languages (IBM360-CSMP, SL/1, ACSL etc).

Basic: I've used this since the days when it escaped from Dartmouth College and appeared on the GE remote service in the 1960's. Also I met it again on Commodore PET and VIC20 machines, and used it for some industrial test equipment using "6502" CPUs. Now currently prefer Delphi/Pascal.
However, I have recently been using VBA (Visual Basic for Applications) in Excel Macros.

CSMP: Became very expert and worked extensively with this IBM originated, Fortran based, Continuous Systems Modeling Program. Now for a CSSL (continuous systems simulation language) I would probably recommend Simulink as part of MATLAB or one of the open source alternatives such as SciLab/Scicos or SciCosLab). I was also was involved with the use of SL/1 as the basis for the digital side of a hybrid computing environment.

Forth: A very different language environment, I used it to create very fast machine code for real-time, hard wired applications. Now working in the Matlab environment creates a similar effect of building up a set of modules which can be invoked at any stage.

Fortran: This was the target language of CSMP so it was much used, but not recently. Pascal (Delphi) covers the programming needs now. Before Fortran, I used Mercury Autocode (London University), and had a brief encounter with K-code for the Ferranti KDF9 machine.

GPSS: General Purpose Simulation System: This was a standard tool with IBM machines for simulating discrete event systems. My McSimAPN covers very similar applications.

Java: Available and a little experience.

Mathcad: from PTC, was MATHSOFT is my preferred means of providing well documented, usable models to the customer for design methods and performance calculations. Its flexibility allows everything from simple arithmetic to solutions of matrix and non-linear differential equation sets. It also has several methods for numerical integrations, making it well able to perform many of the functions of simulation languages.

Pascal: Currently using Borland's Delphi development environment, with its object oriented framework, to produce simulation tools and models for industrial clients. (Version 6)

Simscript: A very powerful language for discrete event simulation. Now would select its successor, Modsim III (also from CACI), for a really big job, or Extend (from ImagineThat Inc) for an easy interface with extensibility. There are others, of course, which might suit equally well.

Spreadsheets: Sometimes a spreadsheet is the tool of choice. I use Microsoft Excel as customers require.