The more I use Google Docs, the less I have to deal with sending attachments back and forth. While attachments' days may be waning, they're still very much a part of most people's email experience. Here are five things you may not know you can do with Gmail to make sending, receiving, viewing, and finding attachments easier:

1. Drag attachments in
Simply drag files from your desktop right into the message you're composing and they'll upload from there. (Make sure you're using Google Chrome or Mozilla Firefox 3.6 for this to work.)

2. Select multiple attachments
Attaching multiple files one by one is no fun. Instead, just multi-select the files you want to attach by holding down the Ctrl key (or Command on a Mac) and clicking on each file you want to attach. Holding down the Shift key will select a continuous list of files.

3. Never forget an attachment again
Gmail looks for phrases in your email that suggest you meant to attach a file (things like "I've attached" or "see attachment") and warns you if it looks like you forgot to do so. Every day, this saves tons of people the embarrassment of having to send a follow up email with the file actually attached.

4. View attachments online
When you receive an attachment, sometimes you just want to view it and there's no need to download or save to your desktop. The Google Docs viewer allows you to view .pdf, .ppt, and .tiff files in your browser. Just click the "View" link at the bottom of the message.

5. Find that long lost attachment via search
If you're looking for an attachment someone has sent to you, Gmail's advanced search operators can help you find what you're looking for quickly and accurately.

A couple examples:
  • To find all messages that contain attachments: has:attachment
  • To find all messages from your friend David that contain attachments: from:david has:attachment
  • To find all messages that have .pdf attachments: has:attachment pdf
  • To find a specific attachment named physicshomework.txt: filename:physicshomework.txt