Sending emails in public WiFi spots can be risky if they are not encrypted in secured channel. When you send them over a WiFi network, it creates the opportunity for hacker to grab your valuable data. This is understadable since public WiFi spots are built for convenience, not for security. If you are looking for a solution to send your data securely, Secrets is probably great solution for you.
Secrets is a free online service that allows you to send emails with encryption. In order to use this service, you must register and login by using Gmail account. Once you have login to this service, you can compose an email by clicking on Compose button, then type the recipient email address and message, follow by click on Encrypt & Send button. A window will be popped up asking you to set a password to decrypt the message. You must remember this password correctly as it will not be saved in the database. To acknowledge the recipient of this password, you need to share it via instant messenger, voice, SMS and etc. The recipient will get an email notification and he needs to click the link as specified in the email in order to retrieve the message. The retrieved message is in encryption format and to decrypt it, the recipient must enter the password as provided by sender.
Secrets uses DES encryption algorithm with keys at 64bit by default. However, it provides few other algorithms such as Triple DES (128 bit), AES-Rijndael (up to 256 bit), Blowfish (up to 448 bit) and ArcFour (up to 2048 bit). You can choose either one of these algorithms as your preference for a secured mean of sending email especially in public hotspots.