Sequence Matrix allows you to easily concatenate gene datasets. A spreadsheet-like interface displays what you've assembled so far; TNT, Nexus, FASTA and Mega files can be dragged into the application to add them. Your entire dataset can be exported as TNT or Nexus files.

To find out more, please see our introductory screencast of Sequence Matrix on YouTube. We've also made available a presentation on Sequence Matrix (delivered to the Hennig XXVIII conference in June 2009) and the paper we wrote describing Sequence Matrix in Cladistics.

The source code for this project is available on GitHub.