We carried out ab initio molecular dynamics simulations for the three cyano-based ionic liquids, 1-ethyl-3-methylimidazolium tetracyanoborate ([C(2)C(1)Im][B(CN)(4)]), 1-ethyl-3-methyl-imidazolium dicyanamide ([C(2)C(1)Im][N-(CN)(2)]), and 1-ethyl-3-methylimidazolium thiocyanate ([C(2)C(1)Im][SCN]). We found that the [SCN]-based ionic liquid is much more prone to pi-pi stacking interactions as opposed to the other two ionic liquids, contrary to the fact that all liquids bear the same cation. Hydrogen bonding is strong in the dicyanamide- and the thiocyanate-based ionic liquids and it is almost absent in the tetracyanoborate liquid. The anion prefers to stay on-top of the imidazolium ring with the highest priority for the [N(CN)(2)](-) anion followed by the [B(CN)(4)]anion. We find that experimental viscosity trends cannot be correlated to the hydrogen bond dynamics which is fastest for [B(CN)(4)](-) followed by [SCN](-) and [N(CN)2](-). For the dynamics of :the cation on-top of itself, we find the order of [B(CN)(4)](-) followed by [N(CN)(2)](-) and finally by [SCN](-). Interestingly, this trend correlates well with the viscosity, suggesting a relation between the cation cation dynamics and the viscosity at least for these cyano-based ionic liquids. These findings, especially, the apparent correlation between cation cation dynamics and the viscosity, might be useful for the suggestion of better ionic liquids in electrolyte applications.