I was recently asked this question:  Traditionally one of the ways our business has promoted our products is via a local letter drop. Is there a more cost-effective way to promote our products to a wider audience?

There are certainly other ways of promoting your business.  Without knowing the retail sector you’re in, here are some ideas:
Ramp up your bag stuffers.  Change them regularly and hand them out to every customer who purchases in your store;
Ensure you capture customer’s email addresses so that you can send out emails, offers and newsletters;
Start a facebook page, ensuring you spend money on facebook ads targeted towards your market ie geographic, gender and age group; 

Place regular classified ads in your local papers rather than full display ads.  The fact that you’re always there impacts onto people’s memory;
Start a blog and include videos of your products/services, funny things that happen in your store, customer questions and answers.  You can run the videos across youtube and include the links into your blog, website, newsletters, instore plasmas or ipads, facebook page, twitter ...
Google your business name and ensure you update every directory your business appears in.  Include email, website, contact details, about us, photographs... everything you can;
Consider registering with various smartphone apps – eg. Foursquare, Urbanspoon or other relevant apps for your retail sector;
QR Codes:  Quick response codes (known as “QR” codes) are a very convenient way to display a small bit of information that is easily scanned and processed typically by mobile devices. Allowing physical items to almost become interactive, by providing information that is easily scanned like a website URL.  You could put your QR code on billboards outside on the street, or bus shelters while waiting for public transportation.  You can place these little codes anywhere.  People with free scanners on their phones (iPhones, BlackBerrys, Androids, Nokia, etc.) can quickly scan the QR code and find out more information, like opening up a website;
Own your niche.  Be seen as the expert.  Write articles for industry publications, blogs, local papers.

The key is to measure everything so you know exactly what works.  Don’t be like so many businesses who scattergun their marketing and have no idea which segment works. These are just some of the additional methods of marketing you can use.  

There are sooooo many more.  Just start thinking about where your customers hang out and how you can reach them.