## Javascript, 85

    for(r=Math.random,s="",i=5;i--;)s+="bcdfghjklmnpqrstvwxz"[20*r()|0]+"aeiouy"[6*r()|0]

If run from the console, output is shown. Explicit display would add `alert(s)` at 8 chars, still shorter than the other JS solutions.

Thanks C5H8NNaO4 and Howard!