Bag packs are a really good way of making cash. However, we have also recently done sponsored walks/bike rides/swims (including writing to local businesses to ask for sponsorship), car boot sales and raffles. We also have a container in every detachment where everyone puts their spare change. You won't get a massive amount of money from this but every little helps....
Depending on what you want to spend the money on you could get some from your local council, Round table, Masons or Lions (or whatever you have in your part of the World).
One of our local detachments just got over £400 towards a new standard from the Round Table - providing they paid the rest.
These groups raise a lot of money for charity throughout the year in a variety of ways and are keen to receive bids to spend it.
If you are putting the money towards something good like equipment or a trip, which will raise a bit of publicity for you both they are even more likely to help out.
Try approaching local businesses for sponsorship. My 2ic does this sort of thing a lot at work for other charities and has started doing it for the det as well. As a result we've got kit out of Ikea and a few other local businesses. It depends what you want the money for.