For a long time I’ve thought: it would be great if GReader handled journal articles more efficiently. Rather than going from link in GReader -> article at journal -> CiteULike bookmark -> back to GReader, how about “post directly from GReader?”
With Google Reader’s new send-to feature, you can do just that. See this forum post for the details. Also, take a look at this how-to for a quick way to post to CiteULike by entering a PubMed PMID, DOI or ISBN identifier in the address bar.