The runners are contacted by a Johnson from corp A. They are to meet a person when contacted, and escort this person to a location in Denver. He is to be protected at all costs, and travel should be as inconspicuous as possible. Enough payment will be made up front to cover the runner's fees for most reasonable precautions (whether they try to do fake IDs and get tickets on a jet, pay off a Panzer smuggler for travel, or what have you), with full payment upon delivery.
*Background*
The contact is a wageslave for corp B. He was 'promoted' to Information Courier Specialist, which is a fancy way of saying he has lots of headware memory, encryption for the memory, and a cortex bomb.
Said wageslave worked at a research facility for corp B. Since the research was supposed to be kept under tight wraps, the facility had no Matrix linkup. Instead, all data transfers were done by this courier, physically taking the information from one facility to another. In this case, the research is nearing completion, and the researchers want a full backup delivered to a safe location.
Unfortunately, the wageslave was originally a plant who works for corp A. His 'promotion' was a fluke, and up to this point he's been watched too carefully to ever get at any of the data in his head. This time, corp A knows he's carrying something big (they just don't know what) and has elected to take special measures. The runners were hired to escort him to a corp A safe location in Denver, while the wageslave 'corrected' his papers to make sure the corp B escort personnel will arrive late at his meet location. Thus, the runners should have no problem picking him up.
Afterwards, the researchers for corp B will have a fit. Turns out, their research was
not sanctioned by the corp. Instead, they were fudging their reports, while working on the head researcher's pet project (which had its funding revoked two years ago). Since they can't ask for help from the corp, after lying about what they were working on for years, they only have their own resources to send after the runners.
To further complicate things, you could throw in some government investigation into the activities of corp B. Or, perhaps a specific government has been wanting to get their hands on said research (not knowing it's the pet project instead of what they were supposed to be working on in the lab).
At this point, the runners will be trying to evade at least three groups who are after their mark, and the courier just wants to get this over with so that his head doesn't explode.

(Yes, I've been watching
Johnny Mnemonic too much. Sue me.

)