It has similar offer like TinyUmbrella and iFaith, one thing that separates iSHSHit from the both is the ability to save the SHSH Blobs from iOS device and available in Cydia.
Now let's save iOS 5.1 SHSH Blobs with iSHSHit.
1. Jailbreak your iOS 5.1 device first if you haven't. (Follow this tutorial)
2. Search iSHSHit 1.0.14 in Cydia under BigBoss repository, once you found it then install it.
3. Your device will begin the installation, once it finishes, restart your device and you will then see iSHSHit icon on your Springboard, then open the app.
4. You will see your unique chip ID, and options like to change your model, select the SHSH blob you wish to save. Click Manage SHSH, you will be presented with a list containing all the SHSH Blobs you previously saved.
5. Select the option you wish in the settings pane, click the save button to start downloading and saving SHSH blobs to your iPhone.
6. After iSHSHit is done saving the iOS 5.1 SHSH blob, then click OK on the push notification message.
Hope this post helps and see you in another posts.