Amyl-, Butyl-, and Isobutyl-Nitrite are used recreationally and are referred to as "poppers". They are known for causing a brief head rush, skin flushing, and muscle relaxation. They are sometimes labelled as "video head cleaners" in order to get past the legal restrictions for inahalants, but it's questionable whether they are actually useful as such. Nitrites are packaged and sold as heart medicines in small glass ampules inside cloth. The ampule is broken and the vapors inhaled as emergency remedies for heart / angina attacks.