SiteSucker is a very nice website downloader for the Mac. It allows you to download entire websites to your hard drive, from where you can then browse them offline. This was incredibly popular in the ages of dial-up, and I remember using apps like this on a daily basis. I don't see much of a use for them these days, especially with the advent of 3G networks and mobile devices. SiteSucker, however, is a great "offline browser" that is really customizable and works well.
There are a few settings that you have to tweak before successfully downloading a website. First, you need to tell the application how many levels you want to download. The number of levels basically determines how many links will be followed. For example, if you want to download a full blog, you better use 3 or 4 levels, or you might download all the Internet. I am exaggerating right now, but this is important.
SiteSucker allows you to filter certain file types that you might not want to download. This is the case with video files or archives. You might not need them, and the application allows you to bypass them, so you don't download something that will take a lot of space. You can also customize the way paths are saved and you can tell the app to download some paths and not others.
All in all, this app works really well, and it gives you lots of ways to customize the download process.
You can download SiteSucker for free from the App Store.