So maybe you aren't a hardcore gamer and want to save some cash, so you purchase an Xbox 360 with no hard drive- this would make you very interested in knowing how much memory a Xbox 360 memory card can actually hold. Without some sort of storage, you would have no way to save any games. Unless you plan on trying to beat everything in one sitting, a noble but extreme goal, you will probably want to save and walk away from the television. How much room do you have with an Xbox 360 memory card though?
The simple answer is 512MB. This may seem like a lot when you consider that the last generation of consoles supported only 8MB of external storage. The reason for the upgrade in size is because of the advances of video game technology. More information is needed to be saved and stored, so more space needs to be provided. The problem is that even 512MB really isn't enough for a large amount of gaming, and the money you save in buying either an Xbox Arcade or a refurbished Xbox 360 without a hard drive is negligible when you have to purchase the $30 memory card.
The biggest drawback with relying on the memory card and the amount of memory it holds is that you won't be able to purchase any downloadable content (DLC) for any of your games. While this may not have been such a big deal in 2006 or 2007 when Crackdown and Oblivion were the only games with post release DLC, nowadays almost every worthwhile title on the system is supported after its release with new add ons and adventures. 512MB might hold over a more casual gamer who only plans on playing a few games, but if you want to get the most bang for your buck over the long shelf life of the Xbox 360, forego a memory card and go with one of the newer model of hard drives instead. Your inner gamer will thank you for it.