Coinbase has introduced one of the simplest ways to accept bitcoin payments. They're notable in that it's one of the only Bitcoin platforms in the world that lets you buy bitcoin directly from a US bank account.
From their website:
Payment buttons make it easy to accept bitcoin on any website by copying and pasting a few lines of code. We were really inspired by the Stripe Button and wanted to bring something similar to the bitcoin world.
Payment buttons work well for “buy now” purchases, donations, and shopping cart integration. And since the payment window is embedded in your website, the user never needs to leave your site.
There is a brand new Merchant Tools section on Coinbase that lets you generate payment buttons in just a few minutes.