I used to have some tablets from Holland & Barratt that had seaweed, green tea & stuff in them but I wasn't really taking them religiously. Green tea is meant to speed the metabolism up, reckon I need an electric shock to speed mine up!
I also have Maximuscle protein shakes - 1 a day, I've found my weight loss is better on the weeks I've had them than the weeks I don't (they're not cheap and I can't always get them). I mainly started as according to MFP my protein intake was really low.