A scrying table for an altar or as a portable device. Based upon the instructions within 'Johannes Trithemius - The Art Of Drawing Spirits Into Crystals' from Francis Barett's The Magus, London, 1801.' and particularly useful as a permanent summoning circle for the conjuration of spirits using this method.
But remember, this is just a tool...YOU are the magick. It's there to help you focus, but you still need to do the internal and external mundane work to support your practice. You can buy all the best power tools in the world, but they aren't going to build a house for you. They can make it easier, faster, deeper, more intense,, etc. but at the end of the day the buck stops with you.