Glenn Fleishman explains a tiny tweak you can make in Lion that enables AirDrop peer-to-peer file exchange to work over local area Ethernet and wireless networks. This enables AirDrop for older Macs that lack the right Wi-Fi chips to work with AirDrop out of the box, and it also adds wired LAN access for even those Macs that do have supported Wi-Fi chips. follow link
Extract Directly from Time Machine
Normally you use Time Machine to restore lost data in a file like this: within the Time Machine interface, you go back to the time the file was not yet messed up, and you restore it to replace the file you have now.
You can also elect to keep both, but the restored file takes the name and place of the current one. So, if you have made changes since the backup took place that you would like to keep, they are lost, or you have to mess around a bit to merge changes, rename files, and trash the unwanted one.
As an alternative, you can browse the Time Machine backup volume directly in the Finder like any normal disk, navigate through the chronological backup hierarchy, and find the file which contains the lost content.
Once you've found it, you can open it and the current version of the file side-by-side, and copy information from Time Machine's version of the file into the current one, without losing any content you put in it since the backup was made.
Enable AirDrop for All Macs with Lion
Check out the Take Control ebooks that expand on the topic in this article: