To me, the mix makes the pleasure! I not only play traditional argentine tango, but also electrotango, much non-tango and some alternative tango recordings. On this page, I'll try to list some particularely good tracks/orchestras.
Non-tangos are normal pieces in which a candombe beat (go-go-stop or quick-quick-slow) is clearly recognizeable, and thus are easily danceable. Most people enjoy non-tango in the style they normally listen to (jazz or blues...), and non-tango is a great way of getting beginners to dance: they usually know one or the other pop-/rock song, and find the beat more easily than in traditional tango which needs a certain amount of practice. Also, advanced dancers enjoy non-tango for the variety, and for the fact that those pieces allow to vary the dancing style.
With the help of multiple sources online - to note Shara Fabiano , Jackie and Alex' stream - I composed a list. As of 2011, I'll offer it as an excel version as some of you want to compare to their lists or the like. So here it is:
Alternative Tango Music