Hi Torben,
checked SQL-Ledger a bit more in detail. Quite impressive, particularly the user community from a zillion different countries. However, they're using relatively complex accounting schemes which is a huge overkill for service-oriented companies...
I've seen your post on their mailing list. Are you sure you want to do the accounting of your consulting business with it? I'm running the company of my wife (about 1000 "projects" and invoices per year...) from an Excel sheet, including income statement, profit & loss and balance...
Frank