I've looked at less accounting and played with there free trial. It was kind of mediocre. Most of these posted are invoicing solutions. Here are the other I've looked into:

http://liteaccounting.com/

http://gobootstrap.com/

http://www.netbooks.com/

http://www.freeagentcentral.com/

http://www.clarityaccounting.com/

From here: http://mashable.com/2008/09/21/270-online-business-tools/