I think you would agree that with recent introduction of cloud services collaboration has become easier. Ftp/sftp/scp have become nearly obsolete. Here is a couple of tools that we find useful:
- Dropbox. This is a cloud file service. The first 2 Gb (which is a lot) are free. An essential tool for sharing projects between group members. Indispensible for synchronizing files across various platforms, PCs, Macs, smartphones, ipads, etc. Five out of five stars.
- Mendeley. Bibliography manager. Free. Multiplatform. We share citations and papers (pdf's) between group members; anyone can add and modify references. Mendeley has a convenient option for exporting bibliography into latex .bib file (library.bib). At the moment flaky but still useful. Three out of five stars.