Hill Holdings Ltd is small company in Barbados, in the sunny Caribbean. We are in the vacation rentals business, and we use LedgerSMB's General Ledger module to keep track of our income and expenses.
From a technical point of view, I found LedgerSMB easy to install. Upgrades and fixes come out frequently, and it is very easy to upgrade via a small Bash script that I wrote myself.
NP Broadcast Limited is a UK-registered Limited Company with a yearly turnover of approximately GBP 150,000, VAT registered with 2 LedgerSMB users. We are mainly a services company providing studio and outside broadcast engineering support to broadcasters.
We are a US not-for-profit (http://riverbendmath.org/) using SQL-Ledger and LedgerSMB since 2006 (I'm not sure exactly when we made the switch). We are a small organization: ~15 part-time employees; ~$150,000 annual revenues; 2 users of the ledger. We are still using 1.2.x because my trial transition to 1.3.x did not work out as smoothly as I had hoped. Thus, I have put the transition on hold until I can give it a few days attention. As an organization we believe in and use open source software almost entirely.