Wildmind (http://www.wildmind.org )
By far the best meditation site I've come across.
"This site is set up and run by people who call themselves Buddhist, but we just want to share with you something that we've found useful. If you don't have a religious tradition then there's nothing here that will seem particularly "religious" at all."

Meditation Frequently Asked Questions (http://www.ncf.carleton.ca/dharma/faqs/meditationfaq.html)
A short but insightful discussion of issues for beginners.

World Community for Christian Meditation
(http://www.wccm.org/frame849653.html)
Christian belief and prayer is outside the scope of Breathing Space but this site seems to do it justice.

Mind Matrix
(www.zenblend.com)
A strange one, this. It offers, free, a guided meditation which has the ring of authentic practice, although quite different from anything in Breathing Space. Then it tells you you'll probably need to buy their special Zen Blend tea to boost your concentration! Worth a visit, especially if you like Flash graphics. Dunno about the tea, though!

Meditation Center
(www.meditationcenter.com)
At first glance this is everything Breathing Space isn't! The opening graphic has a beaded guy sitting crosslegged between candles and incense, and it is prone to phrases like 'ascending the violet ray of freedom'. However, it does seem to offer a good package of different methods, and you can buy a CD, book and online support for very reasonable rates.

alt.meditation newsgroup
The widest range of possible topics to do with meditation, from the prosaic and practical to the totally kooky. I'll leave it to you to decide which is which!

This may seem a sparse list, but as I said the majority of sites I've found have been either overtly or covertly (e.g. Transcendental Meditation) religious. I have no argument with these, but would find it hard to offer strong reasons to include some and exclude others. I'll keep looking, and keep adding!