In case you missed this over on the Groundspeak forums last week:

You might have heard of the MAGIC government mapping tool - this is what the reviewers use to check if a cache is in an SSSI etc. It's really useful, but notoriously difficult to use. Well, not any more...

Thanks to Gary & Jane's new tool Magic MapIt!, it's now dead easy. Just stick your coordinates in the box, click submit, and hey presto! A MAGIC map appears with an arrow pointing to your location. The following overlays are visible, and you can zoom in or out by adjusting the figure in the scale box:

Licence Blocks (GB)
National Trust Properties (England)
Woodland Trust Sites (England)
Forestry Commission Woodland (England)
Local Nature Reserves (England)
National Nature Reserves (GB)
Sites of Special Scientific Interest (GB)
Scheduled Monuments (England)
RSPB Reserves (GB)