The course is based on material from the Purpose-Driven Life, that personal gifts and call can be found at the intersection of 5 factors:
Heart (what you're passionate about)
Abilities ('natural' abilities)
Experience (the key experiences that have shaped you)
The course involved a certain amount of 'homework', - e.g. handing 2 other people a list of common natural abilities and asking them to tick the ones they think you've got. For a few people this was a bit threatening, for others it was incredibly affirming - Brits aren't brilliant at giving feedback, or saying 'you're really good at x', and for some this was the first time they'd had any kind of affirmation in certain gifts and skills.
One result of the course was a number of people enthusiastically getting stuck in to new areas of ministry: from pastoral work to youth and children, to making cups of tea and coffee. For others, you could see the lights going on as they realised that what they did in their workplace day to day was using a God-given talent and could be done in His service.
The course has been rewritten and improved, and is now available as a free download courtesy of the lovely people at the Arthur Rank Centre. It's the kind of things we're likely to run again, and I know of one other church which uses it as a follow-up to Alpha. Highly recommended.