It might not sound like the most interesting or romantic of second jobs, and it certainly isn't. But in terms of deriving a second income, there is a lot to be said for envelope stuffing.
If you don't know what it is, really it does what it says on the tin - it is about filling envelopes.
There are all sorts of mailshot companies that require materials to be compiled for sending out, and it can be literally filling envelopes with leaflets, pamphlets and sometimes addressing them too and then posting them.
If you are after a second business to boost cash that requires no major thinking or effort but rather a simple process to be followed then this could be the one for you.
The other advantage is that you can do it on auto pilot so can do it whilst watching the TV and doing some relaxing rather than requiring a lot of effort and focus like some other businesses out there.
There is also always a constant demand for this and you will often see adverts for it online, in the local paper and doing a search on your preferred search engine will also show up opportunities to do envelope stuffing and earn a handy little second income to boost your main income or give you some extra cash.