If you want something smelly, sticky and cheap (and you got access to your mams liquidiser)try this:
2lb approx of brown crumb
a bag of the smelliest trout pellets you can find
a tin of cheap sweetcorn
Grind up the pellets into a fine powder, liquidise the sweetcorn and then mix the whole lot together, it'll take a bit of mixing to get a decent consistency (and you might need to add some water) but what you end up with is a very sticky mix which will hold a lot of particles if required for balling-in or is ideal for fishing with a method feeder on its own.
If you want to add any extra colour or flavour, add it before you liquidise the sweetcorn so it gets spread amongst the entire mix.
PS - Make sure you clean the liquidiser after use!!