A first version of TT toolbox for MATLAB is released. It seems to works also under Octave —- through not fully tested. Any comments, suggestions and bug reports are welcome at ivan.oseledets(dog)gmail.com
All basic algorithms are implemented as a set of short MATLAB functions. You can try to design your own fast algorithm with these routines or test if there is indeed a hidden TT structure in your vector/matrix/tensor. Really high-dimensional black box TT approximation is underway and will be realized soon in the future versions of TT toolbox.
The efficient Fortran (or C) versions of the TT toolbox are under development right now.