Ashtongue Talisman of Insight

Source
This item is a reputation reward; you must be Exalted with Ashtongue Deathsworn to purchase it for from  in Black Temple.

Effective Spell Haste
The effective Spell Haste granted by this trinket is calculated in a fashion somewhat similar to the Sextant of Unstable Currents and Shiffar's Nexus-Horn. In essence, to get the most out of this Trinket, it is desirable to have short cast times coupled with high crit. chance.

The formula for calculating how much Spell Haste one can expect from this trinket on average is as follows: E = 145 * (6 / (t / (0.5 * c))) Where... E = effective +spell haste t = cast time c = critical strike chance

The following Java program can be used to obtain a table of expected +haste for different cast times: public static void main(String[] args) {      float crit; float time; float effective; for(time = 1; time < 3.5f; time += 0.5f) {          for(crit = 20; crit < 55; crit += 5) {              effective = 145 * (6 / (time / (0.5f * (crit / 100)))); System.out.println(" " + crit + "  " + time + " " + effective + " "); }      }   } An important thing to note is that given a high enough Critical Strike chance, coupled with a low enough Cast Time, it is possible that the time required to proc this trinket is shorter than it's duration, in which case the Trinket is perpetually up - in the tables above, such a state is represented by the effective +Haste being >= 145.
 * 1.0s - Arcane Missile(Each missile)
 * 1.5s - Scorch
 * 2.5s - Frostbolt
 * 3.0s - Fireball