We would like to provide cached results ourselves, but unfortunately it is non-trivial to do so as it requires a lot of storage.
We do have a !cache bang that will take you to a Google cache result. To use it, just search !cache followed by the URL. For example, try the search !cache http://duckduckgo.com/.
To use that easily, you can just copy and paste the URL from a result via your browser's' right-click/long tap menu. We are considering offering an easier way to do this from the interface.
Prior versions on GitHub.