Dimensional Storage – The ability to store objects in another dimension.
Devil-Slayer (Marvel) has a cloak that acts as a portal to other dimensions (Official Handbook of the Marvel Universe V1 #3).
The Magician (Marvel) can store a van worth of electronics in The Astonishing Ant-Man #10 (Marvel).
The exterior of the TARDIS has not changed over the decades.
The interior of the TARDIS has changed a great deal over the decades.
The TARDIS is ultimately a transport machine and traveling through not just space but time as well is a complicated process.
Doraemon can pull all sorts of gadgets from his pocket.
Doraemon can pull out the Anywhere Door/ Dokodemo Door that allows him to travel to just about any destination.