From j2 Global Communications:
HotSend makes it easy to email anything to anyone! Now you can share Web pages, reports, proposals, and photos without the hassle of normal email attachments. AND IT'S FREE!
If you're not sure your recipient has a Hotsend viewer, no problem ! Hotsend will "wrap up" a document inside a viewer and send them as one file. Then, when the file is loaded, the recipient has a the viewer and the file together.
An excellent alternative when Adobe Acrobat is just too expensive or complex.