This Demonstration lets you experiment with several temperaments for tuning. Most pianos today use equal temperament, but this was not always the case. Every temperament has unique characteristics that you can test here. All the temperaments were tuned from A4. You can both listen to and visualize the pitches played.
These temperaments are tuned to A for consistency and simplicity, so the locations of wolf fifths and other characteristically out-of-tune intervals might be different. For a description of these temperaments, visit the Wikipedia page for "Musical Temperament".