Q:

Op Amp gain less than 1?

How would I design an op amp with a gain of less than 1? Is this even possible? Also would it matter if I used a non inverting or an inverting op amp? 
I've designed a non-inverting op amp with a gain of 2 like so. Can I modify it to have a gain of say 1/2? 

1 + R1/R2

simulate this circuit – Schematic created using CircuitLab
I'd appreciate some help here. 

A:

An op-amp is not required.  Given the minimal requirements given, a voltage divider will do.  Gain = 0.5.

simulate this circuit – Schematic created using CircuitLab
If you need to buffer the output, you can just place a unity gain op-amp at the output of the voltage divider.

A:

The non-inverting amplifier circuit cannot produce a gain of less than 1. Inverting amplifiers on the other hand can be built for gains less than 1 because there is no "1+" in their gain equation.
The best approach to making a circuit with a noninverting gain of 0.5 depends heavilly on what your other conditions are. In particular what are the requirements for input and output impedance of the circuit? 
Options may include.

If you can live with the implications regarding input and output impedance just use a voltage divider.
If you need a high input impedance then use a unity gain buffer followed by a voltage divider.
If you need a low output impedance than use a voltage divider followed by a unity gain buffer.
If you need both a low input impedance and a high output impedance (what a non-inverting amplifier normally offers) then use a unity gain buffer followed by a voltage divider followed by another unity gain buffer.

Someone else suggested (in a now delted answer) using two inverting amplifiers. I don't see much merit in that approach.

