I've mentioned this before but images, within a post, can bring referrals once they get onto the search engines - especially Google.On one of my blogs I've now had the best part of a quarter of a million referrals from Google Images and this is a serious contribution to making money i.e. visitors via the images may click on ads etc.
Also I realised, a while back, that images, photos and the like can actually earn you money if you use these as links.
When I was going through some blog stats I noticed that quite a few readers click on images. You can see this on stats such as those provided free by MyBlogLog.
I guess many click on the images to see it a larger size or maybe just out of curiosity. Whatever the reason the thing is that a few will click.
Following this realisation I started using some of my images as links, preferably so that they go to something relative to the picture but also to something that might make me money.
I don't do this with every image as I think this would be overdoing it. If there's a good reason why someone might want to see the picture perhaps a bigger size I leave things how they are. I wouldn't make thumbnails links, for example, because readers would expect to see a larger image when they click.
I think, however, making an image a link is acceptable in circumstances I have stated. It's a matter of balance and not overdoing it - as are a lot of things in life - unfortunately!
For those, who may not know, with Blogger, it's simply a matter of replacing their link with your own choice.I've used an image of Leona Lewis, as she's in the news today, as an example. I simply removed the blue circled area in the HTML and then replaced it with my own link to my celeb blog.

As you will see below I also used target="_blank" in the link to make the link open in a new window and also used alt to say 'Leona Lewis USA no. 1'.

To sum up, for some blog niches, images and photos can:
(1) Bring you referrals and
(2) Make you money.
... a picture paints a thousand words!
Good luck,
Mike.