There are free insect and pest control products and samples available to try.

Insect & pest control
You can get a free sample of Vendetta Cockroach Gel Bait from MGK. They’re giving out one box of four 30g tubes, and this is targeted to insect control professionals.
Click here for a free sample of Vendetta Cockroach Gel Bait.
Older offers
These have been running for a while, and still viable.
Nikwax is giving away free Waterproofing Wax & SkitoStop After Sun insect repellent, but you have to work for it (just a bit). There’s a quiz, and you have to get the questions right, but they let you change them if you answer wrong. These seem to be full size products.
Click here to take the Nikiwax quiz.
Anderson Windows is giving away free screen samples to protect your home from bugs.
Click here to request a free screen sample from Anderson Windows.
Ecosmart is an organic product line for killing ants and bugs safely, so you don’t need to worry about harming your children and pets.
“Click here to test Ecosmart” will bring you to the survey page, then you request a product to try.
Click here to get a free can of Ecosmart pesticide.
They were limiting this offer to the first 500, but it’s still live.