Cubesats are always secondary payloads, usually jettisoned after the first main stage burn. Their mass is insignificant compared to the main payload, so they usually ride for free.

http://en.wikipedia.org/wiki/CubeSat

So I can't speak for all conditions, but cubesats do not usually ride for free. The prices I've seen are usually in the 50k / unit range. So if you've got a 1U cubesat, expect to spend at least 50k on launch. Part of the reason for this is that there are integration costs for attaching a cubesat deployer to an existing launch vehicle, as well as liability risks, control and thrust timing modifications etc.

If the data it could collect in those 2 weeks was worth $200k, hell yes. Sign me up for 2 launches/month.

heh, i was gonna add the clause *unless you're the NSA or have some deep pockets

i think as long as launches are limited, the asking price will be kept artificially high anyways to render the cost of the actual satellite minimal compared to the launch expenses, regardless if it's $300 or $300,000 going up.