docs: Add quick start online Things to README.md

README.md

@@ -296,15 +296,21 @@ Their TDs are available at the following links:
 -   Counter: HTTP at <http://plugfest.thingweb.io:8083/counter> and CoAP at <coap://plugfest.thingweb.io:5683/counter>
 -   Smart Coffee Machine: HTTP at <http://plugfest.thingweb.io:8083/smart-coffee-machine> and CoAP at <coap://plugfest.thingweb.io:5683/smart-coffee-machine>
 -   TestThing: HTTP at <http://plugfest.thingweb.io:8083/testthing> and CoAP at <coap://plugfest.thingweb.io:5683/testthing>
+-   Presence sensor: MQTT at <https://zion.vaimee.com/things/urn:uuid:0a028f8e-8a91-4aaf-a346-9a48d440fd7c>
+-   Smart Clock: CoAP at <https://zion.vaimee.com/things/urn:uuid:913cf8cb-3687-4d98-8d2f-f6f27cfc7162>
+-   Simple Coffee Machine: HTTP at <https://zion.vaimee.com/things/urn:uuid:7ba2bca0-a7f6-47b3-bdce-498caa33bbaf>
 
-All of them require no security mechanism to be communicated with and have the same behavior from CoAP or HTTP endpoints.
+All of them require no security mechanism to be communicated with.
 Below are small explanations of what they can be used for:
 
 -   Counter: It has a count property that can be read or observed and can be incremented or decremented via separate actions.
     It is also possible to reset the count value, obtain when the last change occurred, subscribe to a change in the count value or get the count value as an image.
 -   TestThing: This Thing exists primarily for testing different data schemas and payload formats. It also has events attached to affordances that notify when a value changes.
 -   Smart Coffee Machine: This is a simulation of a coffee machine that also has a [simple user interface](http://plugfest.thingweb.io/examples/smart-coffee-machine.html) that displays the values of properties.
     In addition to proving a real-life device example, it can be used for testing `uriVariables`. You can ask it to brew different coffees and monitor the available resource level.
+-   Presence Sensor: It mocks the detection of a person by firing an event every 5 seconds.
+-   Smart Clock: It simply has a property affordance for the time. However, it runs 60 times faster than real-time to allow time-based decisions that can be easily tested.
+-   Simple Coffee Machine: This is a simpler simulation of the coffee machine above.
 
 ## Documentation