Google gave me a Cr-48 about a month ago. I like it. Its simple and powerful. The temptation to fuss and muss has been removed. However, one of the things I miss a lot is hotstrings that I set up in autohotkey. So for instance typing "asap" will autoexpand to "as soon as possible" no matter what software I am in. I cannot do that in Chrome OS. Google Docs has something under tools>preferences>automatic substitution but that is only specific to Google Docs. I want to have hotstrings everywhere.
You can try Popchrom
Note: I haven't tried this on my Cr-48 yet