This is a Wang 600 programmable calculator. A sticker on the back reveals that it was made in 1974, and serviced on 1978. It seems to function properly, despite the bits of what appears to be wood and other crap which has fallen under the keys. In addition, the cassette drive has some shavings in it, and has been drawn on with pastel. There are more of them in a pile somewhere, and this particular one was the most accessible one to blog about.
What makes this really interesting (aside from collectibility) is the fact that there are two i/o ports on the back, and that there is a Fortran compiler online for it, creating many opportunities for hacking and the like. Also, the name of the system leads to many rather amusing/crude jokes ("We at the ACCRC would like to show you our wangs").