I know from your correspondence that many of you download my puzzles to keep your brains active and sharp. If this describes you, I think you’ll like the new book by Joshua Foer called Moonwalking with Einstein: The Art and Science of Remembering Everything [ Self disclosure: I should mention that I once lunched with […]

Fans of my variety slitherlinks will enjoy these two new sets of puzzles, based on two different Rhombille tilings supplied by reader Lars Huttar. The first set (shown here) is a basic rhombille tiling with intersections containing 3 and 6 vertices. The second set contains intersections of 3, 4 and 5 vertices. Rhombille Set #1 […]

Here’s another crossfigure puzzle from one of our readers. This puzzle is by Paul-Olivier Dehaye, of the mathematics department at the Swiss Federal Institute of Technology. Thanks Paul! Download the PDF Do you have another good original puzzle to share? Let’s see it!

Rolf wrote in with the following message for the readers of KrazyDad: Here is a link to a website that has photos of the large clay tablet unearthed recently by archeologists from the University of Brattleboro. Here is a link to a photo of the tablet on Flickr. The tablet, which measures 16 inches by […]

Here is my estimate of worldwide Twitter volume since November 7th. A few things to note: * The growth in overall tweets per day has slowed a lot since the beginning of the year – it started to stall a bit in the autumn. Recent Comscore results show that visits to the Twitter website began […]

This weekend I compiled the data to produce the above graph, showing the level of activity on Twitter. I figured this out using a commonly known method. Every tweet has a unique id number, for example the 20 that appears in the URL of this tweet which kicked off the service: http://twitter.com/#!/ev/statuses/20 Assuming these id […]

A more individually tailored version of the famous 411 scam arrived in my inbox this morning. I thought I’d share: From: customerservice@citibank-group.com Date: Fri, Oct 1, 2010 at 12:18 AM Subject: SUB: CUSTOMER INFORMATION * Attention The Genealogical database of our deceased customer Mr. Bill Bumgardner has revealed you as his family relative. Kindly confirm […]

Hey folks, I’ve added some new Bridges puzzles to the site. In Japan, Bridges are known as Hashiwokakero which means “Bridge Building”. They are also known here as Hashi. In these puzzles, you are presented with a collection of numbered circles, which represent islands. You connect the islands with bridges to form a network of […]

Some weeks back, I used Facebook’s open graph API to read about 1.2 million names from Facebook users. I used it to construct this file, which shows, for each name, the number of times it occurs, the number of times it’s used by males, and the number of times it occurs in females. To keep […]

My Whitney Music Box made the front page of Reddit today, and is being picked up by a few other sites. Here are some blog entries I wrote about it, back when I was working on it: Visual Harmony A φ Fractal Dan Piker’s Whitney Variations HensTooth Discs Whitney Music Box simulation Also check out […]