pubtex is a tool that allows you to convert pubmed IDs in your latex document to bibtex entries. It's primarily based on javascript with almost no server side processing.
You can access pubtex at http://pubtex.herokuapp.com/. For a demo, hit the example button to load a sample latex document.
Feedback and suggestions are greatly appreciated. If you do have any, please drop me a line at (wagih(at)ebi.ac.uk) or open an issue on github.