I don't think any keywords, in themselves, will penalize you with the search engines; The keywords do seem to be relevant to any websites to which they point, though, and you will want to stick only to "white-hat" advertising practices--that is, you want to avoid spamming people, overusing redirects, or ads that produce pop-ups or pop-unders. Those are good ways to anger, upset, or frustrate visitors... but I do not know if search engines have added that to their criteria.
You can check out sites like Alexa, though, and do what are known as "reverse keyword searches." Those will help you decide which keywords are being frequently searched, and that, in turn, can keep your links that much more relevant and useful.
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I don't think any keywords, in themselves, will penalize you with the search engines; The keywords do seem to be relevant to any websites to which they point, though, and you will want to stick only to "white-hat" advertising practices--that is, you want to avoid spamming people, overusing redirects, or ads that produce pop-ups or pop-unders. Those are good ways to anger, upset, or frustrate visitors... but I do not know if search engines have added that to their criteria.