If you're the sort who overspends at the mall, you may need a firm reminder to watch your budget. How does an ever-vigilant handbag sound? Finder.com.au could soon make one: meet the iBag, a prototype carryall that locks you out if it believes you're going to splurge. The Arduino-powered bag automatically shuts tight at those times you're most likely to shop. Outside of those moments, it uses GPS to warn you when you get too close to favorite stores; ignore the alert and it will both record when you take out your wallet as well as send a text message to a trusted partner. iBag is primarily a publicity stunt meant to highlight the dangers of credit card debt, but it might become a reality. The site is asking potential customers to register their interest, and it may sell both men's and women's versions of the bag for $199 AUD ($173 US) if there's enough demand.