Mestrelab has released a series of freeware applications that you might find useful.
- MestReJ: A free tool for the prediction of vicinal proton-proton 3J(HH) coupling constants.
- MestReS: a virtual NMR simulator package intended to allow students to learn and practice the NMR instrumental techniques while saving rather expensive spectrometer time and avoiding equipment damage due to improper use.
- EXSYCalc: is a free program intended for the study by NMR of molecular systems undergoing chemical exchange. It does a quantitative analysis of the experimental intensities of the NMR peaks obtained in EXSY experiments to calculate the magnetization exchange rates k' of the exchange equilibrium (related with the reaction rate constants k ).