Yesterday I gave you an idea of why spam is not smart marketing, but I also promised you I would give you some inexpensive, but powerful, alternatives that still give you a decent ROI, when done correctly.
25 Ways to Not Spam

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Although some large companies seem to forget this, like ToysRUs, you are very much negatively impacted by being associated with spam.  Most everyone I know hates spam.  In fact, Americans hate spam enough to make fighting it a billion dollar industry.
From a 2003 article on fighting spam:
"Given an environment where virtually anyone can purchase a [...]