bit.ly is great. Great in you can change your random text for your short url to whatever you like unless it's already taken. Another thing is bit.ly generates the 2D barcode QRcode (Quick Response code) which can be read by most smart phones.
This then can be used on flyers, cards or my favorite playing card size stickers and stick them where people can walk by and scan. I haven't seen what DA looks like on iPhone yet. Don't have a smart phone.
The nice thing about bit.ly it gives stats which tells you if they used your QRcode to get to your site. I've already put up a few in Toronto along Queen Street near John and up by the museum before heading to AN.