The Rockwell AIM-65 was a wonderful learning tool. I learned 6502 assembly language, more BASIC than anyone should know, and this amazing language called Forth which I used from them on in designing instruments for research. The AIM-65 had everything you needed; a monitor and HLL (BASIC, FORTH, or PL/65) in ROM, a 20 character display and a 20 column thermal printer. I eventually bought a Heath video terminal in order to see more and used the cassette interface with a little tape recorder to save work. I extended the Forth compiler and added another PROM with a Cubit Prom programmer that fit the AIM and then a Little Buffered Mother to allow bigger projects like adding an AMD9511 floating point processor and floating point support for the Forth and a long wasted effort to make a better analog vector display (inspired by the Battle Zone machine) just as raster displays were getting cheaper and higher resolution -- they still don't look as good in 2005 as a vector display.
Here is everything that came with it plus some extras. The AIM-65 is the keyboard you see and the board above it with the paper roll on the left.
This is the AIM-65, the Little Buffered Mother, and the Cubit PROM programmer. Pretty cool. The buffered mother could hold four large boards with edge connectors like the STD Bus.
Since you were wondering, yes there is an AIM dream machine. If you see one of these, contact me poste haste. The AIM-65 was very successful and Rockwell followed on with commercial development systems - which was the idea in the first place. But a better AIM was needed as well. Along came the AIM-65/40 with a 40 character fluorescent display and a 40 column printer and I think there are three 65C02 processors to unburden the main CPU. One ran the printer and the other ran the display. So, it had smart peripherals and you cold actually buy the printer and display modules as RM65 or Micro65 boards for a little card cage. Thus you develop your entire project or product with your AIM-65/40 then put it into production using the modules that perform exactly the same functions with exactly the same code.
Here is a 65/40 with either an RM65 module or a Microflex 65 module. I can't tell them apart. The Microflex was available with either the Eurocard format or the edge connector STD bus style. Eurocard connectors were very pricey. Almost all of these went into industry. Those that have not been thrown away are gathering dust somewhere.