Can I use an external graphics card on my laptop?

I would have thought producing one would be fairly easy. I'm not familiar with the insides of a laptop - I know the very basics, i.e, the bits that can be worked out using common sense, but I would have thought that technology of our time would enable such a thing as an external graphics card to exist for a laptop. Surely its just a matter of taking the technology used in a computer where the graphics card is easily removable, and compacting it so it fits inside a laptop? Or am i grossly under-estimating the processes involved?

I have been looking for one for a while, nvidia should really make one they'd get loads of sales.

The only one that has been publicly rumored is the ASUS XG Station, and that has been in development for well over a year and a half - and it still has not been released.

 

I suspect the engineering is not trivial - ASUS is one of the best computer engineering firms in the world - if not the best out there - and it seems to have had trouble producing one of these.

 

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

 

 

ejn63 is correct. Today's mid to high-end video cards require a direct power connection to the PSU & virtually all interact with system RAM. It's no small undertaking to create an external one. 

Here is the latest on the XG Station http://www.hardwarexl.com/news/news_from_affiliates/asus_xg_station_closer_to_release_@_tcmagazine/ .