I have a couple of specific research interests which I'm either planning on working on, or would be interested in working on with other people. These are generally of at least a slightly-academic bent, but aren't a terribly high priority in my life.
Version control in OpenDocument Format. The OpenDocument Format (ODF) is an XML-based format for exchanging office files, such as word processor documents, amongst users of different software. While ODF does include features such as change tracking, it does not include real version control.
The basic blocks of version control systems are the abilities to work out the differences between files (deltas), and then do meaningful things with those deltas. As an XML dialect, there are special problems with generating these deltas (see: Towards XML version control of office documents: Borghoff, Rönnau & Scheffczyk, Proceedings of the 2005 ACM symposium on Document engineering).
As a beginning, it would be interesting to generate a specific set of tools to work out the meaningful differences between ODF files, and be able to manipulate those changes in a manner which is user friendly.
Selling Free Software. I wish to do an investigation into the economic realities of attempting to run a business based on the sales of free software (as defined by the FSF): that is, to research those businesses whose business model is that of a "traditional" software house.
While it is clear that business models which support the development of free software do exist (witness the relative abundance of modern free software), it's less clear that a model based around direct sales can support such development. The first phase of this research would involve attempting to find businesses attempting such a business model.
Security in PHP applications. PHP is not a language known for security: while the language itself has encountered a few security issues over its lifetime, this reputation has mainly been gained due to the applications written in it.
Projects such as "Hardened PHP" attempt to address flaws in applications by auditing and making changes to the language, "PHP Sec" (a dead project now?) attempts to spread best practice amongst programmers.
An interesting half-way house would be provision of libraries providing an abstraction to basic services that PHP ought to provide, but using an API such that the programmer is encouraged/forced to into "best practice".
I will update this page if and when these projects are started, and when they begin to produce output. If you're interested in any of the above, or in subjects in similar areas, I would be very interested to hear from you - feel free to contact me.