[mpoulton]

You can do this, but you'll need to replace the 30A breaker with a 20A. You can run four wires: two hots, neutral, and ground. The 120V loads go from either hot to neutral, and the 240V receptacles (make sure to use a 240V receptacle type!) go between the two hots. I installed a few circuits like this in my old shop (not re-using an old circuit, though). The way I arranged it, I installed double gang boxes. Each box had one duplex receptacle, and one 240V 20A receptacle. The duplex was split so the top half was on one hot and the bottom was on the other. That way I could run two high-current 120V tools from the same outlet.

 

[mpoulton]

Don't you mean from either hot to neutral?

Yeah, I can't believe I wrote that. Edited.

 

[mpoulton]

I would like to see the reference where you found this.

The NEC is generally restrictive, not permissive. If something is not prohibited by the code, it is allowed. Note that HouseHelper did find a provision that specifically addresses this, though.

 

[mpoulton]

here it is straight from the nec

210.4(C)
Line-to-Neutral Loads. Multiwire branch circuits
shall supply only line-to-neutral loads.

Exception No. 1: A multiwire branch circuit that supplies
only one utilization equipment.

Exception No. 2: Where all ungrounded conductors of the
multiwire branch circuit are opened simultaneously by the
branch-circuit overcurrent device.

I don't see any ambiguity whatsoever. A MWBC with a double-pole breaker is clearly permitted to supply both 240 and 120V loads. That's the entire point of Exception 2.