The Glacialtech Alaska is a tower style heatsink with an extruded copper base plate that has been machined flat.
The aluminum fins of the heatsink are shaped so hexagons are formed by the stack. The fins feature scalloped leading and trailing edges not to mention perforated fins based on design criteria layed forth by The Japanese society of mechanical engineers paper "Forced air heatsink with new enhanced fins". Six 6mm diameter heatpipes pass through the fins in a sort of "V" pattern which is apparently done to reduce airflow resistance.
The Alaska ships with a 120mm PWM fan, stands 156mm tall and weighs 740 grams.