eliminating trailing commas

Just to add one more...
Since you don't appear to be linking each element,
how about to_sentence from Active Support?

tags = %w{shoes shirts socks pants}

=> ["shoes", "shirts", "socks", "pants"]

tags.to_sentence

=> "shoes, shirts, socks, and pants"

<small><%= tags.to_sentence %></small>

Or, without the "and"

tags.to_sentence(:connector => nil)

=> "shoes, shirts, socks, pants"
Although, this inserts an extra space
before the last element for some reason.

- Brian