Don't know about anyone else...but I most definitely have experienced light acid-ish hallucinations from strong brownie's / cookies (cartoon vision, etc). Obviously it depends on the herb, but it's often A LOT heavier than takin' a little toke off a joint... and the only thing it was laced with was weed. People commonly claim that their brownie/cookie was laced because they trip out...in fact it's nature's own THC doing that to ya! [video=youtube;CU6AVtQethw]http://www.youtube.com/watch?v=CU6AVtQethw[/video]