Try GliphMe now: gliph.me
GliphMe lets you create a web link that anyone can use to start chatting with you on your iPhone or Android. When someone clicks one of your links and sends you a message, you will be notified by the Gliph app. You can reply immediately wherever you are from your mobile device. Gliphme links are short and look like this: gliph.me/xyz. (inactive example)
When someone clicks a GliphMe contact link they are presented a chat box that lets them communicate with the link creator.