My friends over at Prima Coffee posted this today and I thought it was too good not to share:
DIY cold brew for $30! You’ll need: Aeropress with 2 filters, bottle, sewing needle, sharp knife, water, ice, and coffee.
 Empty bottle and cut off bottom.
 Remove bottle’s cap and puncture w/ needle. Replace cap. Test flow by filling w/ water and watching rate, aiming for about 40 drops per minute.
 Wet filter and assemble Aeropress, filling w/ 45 g (9 tbsp) of medium-fine ground coffee.
 Moisten grounds and stir gently, subtracting water used from total water dose. Level coffee bed with finger.
 Trim second filter to fit inside of Aeropress and place atop coffee bed, pressing softly to level.
 Place Aeropress on jar and mount bottle on top.
 Fill bottle w/ 300 g (10 oz) water and 200 g (7 oz) ice.
After bottle has emptied, serve coffee over ice.