Chrome: Incognito mode is great for keeping your browsing habits secret, but by its definition, it's bad at keeping track of sites you frequently visit. Hush allows you to keep private bookmarks without worrying about others finding them.
The extension is simple. Click the lock icon to create a bookmark. Create a password for it and the bookmark will be saved, encrypted locally on your drive. Later, when you want to pull them back up, click the lock and enter the password.
You can actually set different passwords for each bookmarks and only the sites connected with that password will be pulled up. In that way, it's sort of like an elaborate tagging system, but since the passwords are the only way to access your bookmarks, it's effective at preventing other users from finding your stash of secret gift ideas.
Hush [Chrome Web Store]