Yes, the free, awesome and easy 3D modeling app 123D has now been extended to 123D Design, available for OSX, PC, iPad AND Web App. That's four times as fantastic with interoperability between all four and the rest of the 123D suite making it easy for you to design for 3D printing with Shapeways.
With Autodesk 123D Design, anyone can have fun designing and making things. Whether it's a new design of your own, replacing a part of something you already have, or reimagining something so that it's just right for you, with 123D Design you can create a digital model of your idea and then directly 3D print or fabricate the things you want, just the way you want them. And the way you work with 123D Design is similar to how you work in other everyday software you're familiar with, so you can avoid frustrations and enjoy the process of making things.
I have had the opportunity to play with an early edition of the software and it is easy to learn and export to 3D print with Shapeways. This is a perfect tool for someone starting to design their own products as we will be sure to cover in our Design for 3D Printing 101 series.