Aside from 50+ decks, I also keep on hand many Tarot tools, as I know other readers do. Some tools are for the care and feeding of the cards themselves. Others are for readings and daily practice. Here are a few tools in my "Tarot Kit."
Deck Care: Nancy Antenucci taught me the very first time I ever got a deck that Tarot cards you're going to make use of really don't belong/enjoy being in the cardboard box they came in. You never know who's touched it with what energy, it's flimsy, and it shows a lack of deck care. Never mind the fact that shoving them into that tight little box often causes damage to the cards themselves. I have several scarves and Tarot card bags that I employ for every deck I've taken out of its packing (which is, I'll admit, more than half of them). Finding a good "home" for your deck is also a good way to bond with your deck. My first deck wanted a purple-and-gold goddess scarf, for instance. It just seems to make the energy of the deck calm and "happy."
Another tool I use is sacred stones. While I am not entirely versed in the many attributes of different healing stones, I do know a few, and most importantly, I know amethyst. I have some tumbled amethyst stones that I bought in bulk once, and when I am finished reading with a deck, I will set an amethyst stone or my amethyst wand on top of it to cleanse the energy from the deck. Amethyst is imbued with spiritual and cleansing properties. I do have to admit I am not a terribly good caregiver to my healing stones, however. I basically keep them in a small pile with white quartz and hope for the best as far as cleansing the stones themselves goes. I really should have them settled with some selenite.
I will also use my own chakra energy to cleanse the cards sometimes, though this is a bit more draining, so I don't do it very often anymore. I realize this may be a bit "woowoo" for some people, but a belief in the power of Tarot is really a belief in the divine energy that connects us all together. And the negative energy, of course. Yin and yang and all that.
Sacred Space: It is important to carve out space, no matter how small, for reading your cards, especially if you're reading for someone else. The space should be clear of clutter and clean - somewhere you aren't going to be more worried about knocking over a stack of papers or getting your elbow stuck in a ketchup stain than reading the cards. This will make you, your reader, and your cards more comfortable. You don't want ketchup on your cards, either.
Create an atmosphere conducive to reading and meditation. I have a sage candle I burn, for instance. To cleanse the space itself before a reading (energy or bad tuna sandwich), I will also either use my spray sage from Eye of Horus or burn the real sage I have in an abalone shell (thank you Pyramid Collection). Wafting the smoke around not only creates a pleasing scent, but also chases away any negative energy that may be lingering around.
Offer water to your querent, and have some for yourself. Water also has cleansing powers for your body, and keeps your voice from frogging up. Do not use mind-altering substances when reading the cards and limit caffeine and alcohol intake before a reading. It is not fair to you or the querent if you are not wholly present in the moment.
Tools of the Trade: I always have a Guatemalan Quetzal on me when reading cards (it keeps me grounded - element of Earth and suit of Pentacles/Coins). For those curious about the Quetzal, it is the national bird of Guatemala and also what they call their money. Inscribed on the Quetzal is the word "Paz" or "Peace," which you can see here. I find it both hopeful and calming. The Quetzal usually won't be on the table when I'm reading, unless I don't have pockets. I like to keep it close to my skin, and it is almost always warm to the touch.
Another tool I always have when reading cards is my amethyst crystal (wand). Amethyst facilitates sacred connection, and wands are the seat of creativity and action. I first got it because purple is my favorite color, and I have an affinity for amethyst. I researched its actual properties later. The amethyst wand I keep on the table during the a reading, close to my right hand. I can touch it if I feel my consciousness may be wavering (or wandering), and it also encourages divine energy to join us during a reading.
Tools I do not usually take out, but I have to hand if I feel I need them or for ritual work, are an athame (sacred dagger - suit of swords), a chalice (suit of cups), a sodalite orb (encourages clear thinking, truth, and emotional sharing), an amethyst pendulum (I gave my rose quartz one to someone in need), a rendition of Kali (constructive and destructive forces - the Tower card in the Tarot of Transformation), and assorted sacred stones (white quartz, rose quartz, tiger's eye, obsidian, etc.).
I *mumbles* may or may not have a bald eagle feather from Canada *cough* that floated on the water towards me that I will use to waft sage smoke.
Why don't I usually use these tools? Well, the athame I consider unnecessary, as well as the sodalite orb, because I am all air - Gemini with a Libra Rising Sign and a Moon sign of Aquarius. I don't feel the need to introduce any more air into the space than is already there. The chalice is rather large and cumbersome to a reading, and its absence really hasn't affected anything at all. I almost never use a pendulum for anything. Kali is a goddess energy that is always close to hand (I like to think of it as a shade of God) for me, and... well... I love amethyst.
I'd love to hear what tools you use. Don't be shy!