Are there Solo 401-K-like options for Independent Contractors?

[Brandon Addison]

I've done some reading on the advantages of Solo-401K options (this article was awesome!).

I am hoping to use funds from my adjunct teaching to invest in real-estate and was hoping I'd be able to shelter this income by dumping it exclusively into the Solo 401K. It doesn't appear that the Solo 401K applies to contractors, however. 

Since the Solo 401K isn't an option for me, are there other tax advantaged options that 1. Allow me to significantly reduce taxes on the contracted income 2. Allow me to invest in real estate?