• KrazyDad is working on creating a new type of slitherlink puzzle called Altair slitherlink.  The grid for the puzzles is based on a medieval Islamic tiling.
• Mathpuzzle.com has some new material this week… including some interesting analysis on how many moves it takes to solve a Rubik’s Cube.

I’ve posted before about all of the puzzles available by Jim Bumgardner at krazydad.com. Recently, he’s added thousands of Slitherlink puzzles to his site with varying degrees of difficulty and grid size.

Jim is also looking at variations on the classic Slitherlink puzzle and he’s constructed a hexagonal slitherlink that appeared in a recent blog post.

I’ve come across a couple blogs where people are working on slither link variations. The first set comes from a blog a called *Insert Clever Title Here*. Here the puzzles are called loop-de-loop (which is also sometimes used for slither link.) At certain points in these puzzles there are symbols which place limits on the path through that point. For example, a symbol might indicate that the path must turn at that point or must not turn at that point. To really get the idea, click over and try them out.

The other set comes from zotmeister where the puzzles are called “The One Ring”. The variation here is similar, with the added twist that the dots have clever names. Dots where the path can’t bend are called angel dots. Dots where the path must bend are called devil dots.

Slither Link is a nikoli puzzle sometimes called “Fences.” Slither Link puzzles consist of a field of points in a square grid with numbers inside some of the individual squares. The goal is to connect the points to form a single loop with the constraint that each number must be enclosed on as many sides as indicated by the number. There’s a nice flash tutorial for the puzzle on the nikoli site.

I bring this up because I just came across a great collection of Slither Link puzzles through Passion For Puzzles. Also, if you’re looking for an interesting variation on Slither Link, check out last year’s US Puzzle Championship test. There’s a puzzle called “False Field Fences.” Numbers inside the loop tell the correct number of enclosed sides, while numbers outside the loop indicate an incorrect number of enclosed sides. Of course, before you solve the puzzle, you don’t know which are on the inside and which are on the outside.