TUAW reader David wrote us to ask how he could view .erb files (Rails development) in Quick Look. The fact is, there are a lot of plain-text files with extensions that Quick Look doesn't recognize. It's relatively straightforward to tell Quick Look to treat these files like any other text file and preview them as plain text; it does require diving into plist files and possibly breaking an application, so don't dive in unless you're comfortable and fully backed up. Read on for a short tour of Quick Look hacking basics ...

Mark Hoekstra, blogger and hacker extraordinaire, has passed away at the age of 34 after suffering a heart attack last Wednesday. The sad news of Mark's passing is making its rounds, and we at TUAW would like to offer our condolences to his family, his friends and his readers. Many of Mark's hacks and adventures are thoroughly documented on his blog, geek technique ... evidence of Mark's creative drive and problem-solving ability. He was a geek's geek in the proudest sense of the word.

We've regularly admired Mark's extraordinary determination and imaginative solutions. We'll miss you, Mark.

Thanks, Eliot.

Like most phone cameras, the iPhone's lens is focused for the most general possible use, i.e. nearly at infinity. TUAW reader Daniel Forsythe modded his iPhone to focus a bit closer up so he could use it to read bar codes that he shoots from magazines and equipment labels.

The mod involves breaking the glue that holds in the camera module and rotating the lens to bring the focus closer to the camera. With this hack, he can snap photos of close-in subjects. Check out his Flickr photo set for samples and discussion.

He writes that he plans to make a full mod guide should readers express interest in it. The photo seen here is focused to 0.25".