If you want something relatively cheap, IKEA has been selling them for years for around the $100 mark. The only catch is that it's not easily adjustable. I paired mine with a walking treadmill. Unfortunately IKEA has increased the price to $200 http://www.ikea.com/us/en/catalog/products/50219044/
The problem I find with StandDesk and others like it is that it only has one level, when in reality you need a shelf for the monitor or you get into a situation where you're crouching to stare at the screen or your arms aren't in an ergonomic position.
The problem I find with StandDesk and others like it is that it only has one level, when in reality you need a shelf for the monitor or you get into a situation where you're crouching to stare at the screen or your arms aren't in an ergonomic position.