1. A computer-implemented method for (i) a user to train at least one computer substantially in real-time by performing a series of randomly-performed, self-selected, intentional muscle movements selected by the user, and (ii) the user to label the muscle movements, comprising: a user actuating a user-controlled device according to a series of any randomly-performed, self-selected, intentional movements selected by the user; the at least one computer recording and compiling the user's muscle signals corresponding to the randomly-performed, self-selected, intentional movements of the device, the at least one computer clustering the compiled muscle signals into at least one cluster of signals; the at least one computer unsupervised-classifying the at least one cluster of signals as at least one non-predetermined function of the user-controlled device, without reference to predetermined classifications of muscle signals; and after the unsupervised-classifying, the at least one computer accepting user input to label the classified muscle signals to correspond to the at least one function of the user-controlled apparatus.