Web pages for a project
Technical reports
Conference/workshop papers
Journal papers
Distribute software over the internet
Do not submit the same (or highly similar works) to two publications simultaneously! This will damage your professional reputation. However, you may reuse a portion of the text (e.g., a "definitions" section) in a second paper, subject to the copyright laws.
The case of non-disclosure
If you do proprietary research for a firm, then it is likely that the research results you obtain are never disseminated outside the company. There may be an internal technical report series, or the documents produced by a research group may be cataloged in a company library.