You can now Open a .PSD file without Adobe Photoshop.

Here Opening a .PSD file doesn't mean you can edit layers with this software.

1. Go to your favourite browser and type Pixlr.com .
2. Find the download button of Desktop app and Install on your computer.
3. Select the desired file to open.

I haven't dig down deep in this software. You may found a way to edit layers.

Download here: http://pixlr.com