Magic Forums

I just had something brought up to me today... There's a social site I go on sometimes called GaiaOnline, which is like MySpace almost, except your avatar is this anime character you create and dress. Much like this site, you must at least be a teenager to join. There's a forum that has several topics and thousands of threads covering all sorts if subjects. Within a forum thread that was discussing magick and how people define and use it, I've been having a conversation on the difference between prayer and spell with another user. They brought up a very interesting point... This person said that, from their experience, their spells tend to be more effective and powerful when they don't have a circle cast or any sacred space. So, what's your guys' opinions on that? What's your experience? I, personally, prefer to cast a circle after purifying and blessing the area and I used to actually do this for even simple prayers; it have me a sense of confidence and security. What's your feedback? What do you do?