I use this gem to teach about gems and contributing to open source.

This requires some thought. isn't it?

Adds area and perimeter methods for common shapes.

A module which allows the GENE gyrokinetic code to be run using the CodeRunner framework.

RSpec 2 library to facilitate creating generator specs

Super easy adjustable form builder with formtastic style DSL

a gem to generate an image URL from shortened URLs from common photo sharing tools. Supports twitter/photobucket, twitpic, yfrog, instagram and tweetphoto/plixi/lockerz. It also includes support for the twitter gem, which helps with expanding t.co and bit.ly shortened URLs. Flickr is not supporte...

Takes a state table where the following are defined: state, input+conditions, accumulate-action, pre-transition-actions, and transition-to. It takes that state table and generates very fast parsers. Similar to Ragel. Currently only outputs pure Ruby.

A Sinatra RESTful web-service for sharing RDFized genomic data.

Geocode a text address.

This gem consists two additional geocoders for geokit, Yahoo! PlaceFinder and Google V3. And add support for caching using api_caching gem.

Calculates the geo distance between two locations using longitude and latitude using Haversine, Speherical or Vincenty formula. This is done using Math formulas without resorting to Active Record or SQL DB functionality

This library uses a GeoJolt.com API key to return all zip codes with a radius of the zip code passed to it.

Get users' entire location information (using IP address)

Simple geometry methods on triangles, rectangles, and circles.

Find perimeter, area, circumference, etc.

Gem for geometry

Geometry!

Checks difference shapes info

creates (W)ell(K)nown(T)ext bounding boxes from points