Ease of installation/use is the most important factor here - not performance.
Small is OK as large datasets are not expected.
If you are familiar with Ruby, the RDF.rb library is very quick to get started with; installation via RubyGems is as simple as:
$ sudo gem install rdf
In addition to working with in-memory RDF data, currently available RDF.rb storage adapters include SQLite, PostgreSQL, MongoDB, Cassandra, RedStore and Sesame.
Loading and parsing RDF data from the web also could not be any easier:
graph = RDF::Graph.load("http://datagraph.org/jhacker/foaf.rdf")
See the RDF.rb project page for tutorials, code examples and API documentation.