Side by Side Bicycle Makes Tandems Look Practical – Make Your Own!
Thanks to Instructables, you can also risk life, limb and marriage and build your own Side by Side (aka Socialable. aka Buddy Bike). Start with a standard frame, then modify to put two saddles and a wider handlebar.
Presumably, you’d want to use strong enough wheels and brakes to handle the extra load, too. Oh, and perhaps two sets of brake levers just to make things a little more interesting.
Video after the break…