Update
Now you can use your item ID a life long (Provided that the item has not been deleted). We offer you the option to reactivate your canceled / inactive items. Simply click the Relist button in your sell area or navigate to the item and click edit. It does not create a new item anymore, instead it is updating the old one. If you want to relist the item with a new item id you need to click "Sell similar item".
Useful feature! Can be get a feature to have a watchlist? I keep on bookmarking a lot of the auctions but miss out. Maybe have a email sent when watching a item is coming close to ending.