I got a Lenovo S400 i5-3317U with 1GB AMD Videocard since I needed a cheap, portable, all-around laptop which can do simple video editing and play World of Tanks. I knew I needed more than 4GB RAM, but the shop told me I could try it out first and can trade it for a different one if I wasn't satisfied. It struggled with World of Tanks at the low setting so I replaced it with an ASUS K45VM, which was more expensive and heavy, but a lot more powerful and seemed more durable.
LIKE: very light (including the charger); removable batt; quiet; No DVD
NO LIKE: limited to 4GB RAM! no VGA port; heat and fan noise right away while running World of Tanks in low setting (at 36 fps); the laptop doesn't seem to be durable
IN A NUTSHELL: Get the S400 only if you want a cheaper, weaker ultrabook with a 4GB RAM limit (something in between a netbook and an ultrabook).