I really like Capistrano--it's a great tool for deploying applications of any kind.

A very simple mechanism for reading old URLs and doing 301 redirects to new URLs, based on a spreadsheet.

This morning I put together the first small gem I've pushed to Rubygems, TinyRackFlash, a flash implementation for Rack applications.

DSpace is a pretty capable repository framework, but it has a number of missing pieces in terms of administrative functionality. You can actually do a lot from the web interface, and the command line operations provide some nice tools, but some tasks just aren't supported.