The cube displays logos on it's faces for bitshares and bitcoin. This is because these were the first two cryptocurrencies we supported.

I suppose the choice of a cube is obvious (a cube is a block and the company is called Blocktrades). But the cube with the various crypto faces can also be seen as a symbol for the act of trading one coin (one face) for another (by flipping the face that is up).

I actually really like our existing logo: it has a lot of personal meaning to me. It was originally designed by my coding partner during the development of the Blocktrades code, but I've never seen another logo that I felt captured the essence of Blocktrades' business better.

It's definitely not classical company logo that a graphic artist would design (it contains too many design elements), but I feel it suits our needs. Somewhat humorously, I recently saw the logo for "BlueSky" and it is a blue cube (i.e. a simplified form of our logo).