2. Architectural salvage lots: Yes, there are spendy items at some lots. But, like any "thrift" type retailer, there are also diamonds in the rough, if you set aside the day to find affordable and unique window, doors, gates, and other architectural elements. Try places like Pasadena Architectural Salvage in Los Angeles, or for a nationwide listing of architectural and hardware salvage shops, check out this article in Cottage Living.
3. Reusable building materials exchanges. One example: the King County (Washington) Solid Waste Division maintains an online Reusable Building Material Exchange that offers free paint, free doors, and a $100 vintage sink, among other materials. Other counties in Washington State maintain a consolidated page, the 2Good2Toss Network, with similar deals. Thrifty renovators in the Northeast can check out the Maine Building Materials Exchange.
4. Oops! paint -- that is, paint that was mistinted or returned (unopened) by a previous customer to your local hardware store, Lowe's, or Home Depot, and offered for resale at a steep discount. Not the best choice for a large paint job (you may not be able to find an adequate quantity), but for small hallways, powder rooms, or a small kids' room, a little bit of flexibility can save you a lot of money.
5. Demolishing your old deck to build a new one? Re-use your own material and rebuild with your own, very locally sourced, salvage lumber.
6. Although availability can be hit-or-miss, and you have to have a lot of tolerance for ... flakiness, Craigslist can be a great resource, particularly for landscaping materials such as fill dirt and decorative rocks.
7. Granite remnants. Perfect for smaller-surface projects (e.g., bathroom vanities), at a substantial discount. If you're purchasing a full-size piece of granite for a larger project, the retailer may even give you remnants for use in your smaller projects for free. Free! Granite remnants are generally available from granite retailers; they also pop up with regularity on Craigslist (see #6).
8. Just say no to replacing those laminate counters. Okay, this breaks my no-HGTV rule. But re-painting a laminate counter will give you a completely custom look that won't break the bank. There are no guarantees, though, that the three-week curing period doesn't break your spirit.
9. Modern, attractive, solar-powered outdoor lighting. $7.99 a pop. Ikea, I love ya.
10. Demolition sales. One step "scrappier" than visiting an architectural salvage lot, thrifty renovators can find even bigger savings visiting actual, to-be-demolished homes that are sold piece by piece. Typically these sales are held for one or two days on the weekend at, obviously, rotating locations. Some of these are run by charities such as Habitat For Humanity, others are run by private companies. To find one in your area, search for "demolition sale" plus your approximate location.