I wish I came up with this fantastic idea. SharedEarth is a free site that connects landowners with gardeners and farmers in need of space to grow crops (i.e. starting a home vegetable garden). You can find free access to land in exchange for sharing a little bit of produce with the landowner. In a time of a strong and growing local food movement and concerns about food safety, SharedEarth might just be the most important sharing site of all!

Bartering does have its limitations. Many bigger (i.e., chain) businesses will not entertain the idea and even smaller organizations may limit the amount of goods or services for which they will barter (i.e., they may not agree to a 100% barter arrangement and instead require that you make at least partial payment). But in an economic crunch, bartering can be a great way to get the goods and services you need without having to pull money out of your pocket.
On paper, this sounds a bit like delayed barter, but it bears some significant differences. For one thing, it’s much more efficient than Smith’s idea of a barter system, since it doesn’t depend on each person simultaneously having what the other wants. It’s also not tit for tat: No one ever assigns a specific value to the meat or cake or house-building labor, meaning debts can’t be transferred.
It is said that “Necessity is the Mother of Invention.”  If we ever get to a point where a barter economy is the way goods and services are exchanged, things will come together.  But those who are prepared ahead of time, those who have thought about all of this, will be in a place where they can quickly move to make decisions that will benefit themselves and their family financially.
Bartering for goods and services is a centuries-old art. Recently, the idea of trading with your neighbors and within your community has received a big boost and taken on a modern spin. Combining our often-materialistic, ownership-based society with the Internet’s ability to bring buyers, sellers, and traders together, online bartering has sparked a wealth of new sites and communities.
In England, about 30 to 40 cooperative societies sent their surplus goods to an "exchange bazaar" for direct barter in London, which later adopted a similar labour note. The British Association for Promoting Cooperative Knowledge established an "equitable labour exchange" in 1830. This was expanded as the National Equitable Labour Exchange in 1832 on Grays Inn Road in London.[21] These efforts became the basis of the British cooperative movement of the 1840s. In 1848, the socialist and first self-designated anarchist Pierre-Joseph Proudhon postulated a system of time chits. In 1875, Karl Marx wrote of "Labor Certificates" (Arbeitszertifikaten) in his Critique of the Gotha Program of a "certificate from society that [the labourer] has furnished such and such an amount of labour", which can be used to draw "from the social stock of means of consumption as much as costs the same amount of labour."[22]
You can use bartering to cut costs with your small business or to reduce personal expenses. For example, a handyman can trade services with a hairstylist. Each person is still getting paid for their work, in a sense, and it can lead to referrals to cash-carrying customers without costing a penny. However, the essence of bartering is simply to trade something you have for something you want or need – and you can do this whether you are struggling financially or have a steady income.
While some people may balk at an online community for finding babysitters, I know several parents who say it’s actually very difficult to find a sitter they can trust. BabysitterExchange started in 2000 as a babysitting co-op, and it has since expanded to the point that members use it to reserve time when they just have some errands run, need help tutoring their kids, or want a temporary house-sitter.