The new Sony Ericsson's with decent cameras (macro mode or autofocus on close range) are great for really really quickly entering expenses via the mobile version of the website.
The Sony Ericsson web browser has a neat feature when you come to a file input form; it shows an option to take a new picture with the camera and uploads that into the upload form.

Here's what you do with your Sony Ericsson:

1. Go to http://m.snapexpense.com
2. Log in
3. Click "Enter an expense"
4. Scroll to the Browse... button and click the select button
5. Choose "from camera" (actual wording differs between models)
6. When you've taken a clear picture you come back to the mobile web page. Click "Upload expense image"
7. Done!


There's actually an even faster way of doing this!
You can generate a page which you bookmark and with this page you'll be able to upload pictures (like above) without first having to log in.

1. When logged in to http://m.snapexpense.com
2. Click "Your settings" then "Your enter expense page" and read the notice.
3. Click to generate the URL for you and save that as a bookmark

Now you can go to this bookmark to quickly add a new expense without having to be logged in. The only (obvious) caveat is that when not logged in you can't do anything other than upload expense images.