Every item of equipment that you acquire for your business represents an investment of your business capital. Taken a step further, an item that is not currently being used represents capital on which the current return to your business is zero or even negative (if property taxes and insurance costs attributable to the item are taken into account). For this reason, you want to be sure to limit the amount of unproductive assets that your business owns.
Adopt a practice of taking regular inventories of all of your equipment to confirm each item's current level of use. If you come across an item that you're currently not using, try to determine whether you have a definite future use for the item that justifies the continuing cost of holding it. If you don't foresee such a future use, seriously consider selling or otherwise disposing of the item.
If you're unable to sell an unproductive item of equipment, or to use it as a trade-in on the purchase of an item you need, you may be able to generate a tax deduction by donating the item to charity or by simply abandoning (junking) it.