I’ve been researching how good a fit Redis might be for a project or 2.  One project needs a memory based key-value store generally without persistence, which would seem to suggest memcached.  However, there may be times where persistence across reboots may be desirable and Redis’ atomic operations and data types may also be useful.  Here’s some links I’ve been checking out:

• Software
• redis – obviously
• redis-rb – gem for accessing redis from ruby
• redis-objects – gem for mapping Redis types to Ruby objects
• ohm – gem for creating Redis based object models
• supermodel – gem for ActiveModel descendant that can store to Redis
  
• Information
• Using Redis with Ruby on Rails
• Datastores with ruby: Redis and Ohm (part 1)
• To Redis or Not To Redis? (Key-Value Stores Part 4) | Engine Yard Blog
• Comparing MongoDB and Redis, Part 1 « While I Pondered…
• Comparing MongoDB and Redis, Part 2 « While I Pondered…
• where_redis_is_a_good_fit
• using_keyvalue_stores_from_ruby