PHPBalanceSheet is an effort to implement a web-based accounting package using PHP. It was initiated in response to a real-world situation: when filing a tax return, it is necessary to account for taxable income and tax-deductable expenditure. PHPBalanceSheet will initially fulfill just this role, but ultimately the intention is that it will be extended to encompass many accounting processes and eventually become something similar to a web-based version of, say, Sage Accounts.
If you are interested in helping with the development of PHPBalanceSheet, the first thing you should do is sign up to the phpbalancesheet-devel mailing list.
If you are using PHPBalanceSheet and have problems, support will be available on the phpbalancesheet-users mailing list.
If you are using PHPBalanceSheet and would like to be notified of new releases and other significant announcements, you should sign up to the phpbalancesheet-announce mailing list.