 Support or services: Some OSS projects commercialize by offering support services or new feature development at a cost. Often users, particularly from corporate entities, are willing to pay for specialized training and ongoing support for their use of OSS projects. In special instances, it may even be the case that outside entities are able to pay for the prioritization of specific features. For example, the major mass spectrometry instrument vendors have been providing financial support to both the Skyline and Proteowizard projects to ensure features, support, and documentation are provided for their customers. This road must be trod carefully though; while there is a benefit to allowing sponsored features, and they do benefit everyone once implemented; such a model risks losing control over the direction of an OSS project.