There are alternatives to Tor that have different anonymity and routing protocols.
For example, take a look at I2P, which has been around almost as long as Tor. It has a lot in common with Tor, but has some key differences that may be appealing to some people. I2P nodes are capable of implementing something like an exit node (often called an "outproxy"), but there's no distinction between peers in I2P that designates one as an exit node. The project is more oriented towards hidden services, implementing its internal network, than it is in anonymizing connections to the clearweb. I think it's great that Tor exists, but I wish more people would consider I2P or at least simultaneously hosting their hidden services on both Tor and I2P. And if you really don't like running a Java runtime, Purple I2P exists and is written in C++.
There are also other networks like GNUnet, which slightly predates Tor, which is mostly file-sharing oriented, but with the goal of anonymity. It can do other things too but, from what I can tell, the project never gained much favor anywhere. Nevertheless, it still exists and is being worked on.
And I can't forget Freenet, or what's not referred to as "Hyphanet". I'll just call it Freenet for now because a lot of people still remember it. Freenet's focus is not only on anonymity but providing a distributed data store that is censorship resistant. This at least in part solves the issue of having to be online all the time in order to host a hidden service. It's been a long time since I've used Freenet, but supposedly the community is very good at discouraging crime and other unsavory elements. I haven't used the new iteration called Hyphanet.
All of these projects have significant differences from Tor, and some of these differences are seen by some as fixing significant flaws present in the Tor protocol that Tor can't reconcile. I2P's design of having no peer distinctions, in my opinion, is a vastly superior model for both security and plausible deniability. Its routing protocol also makes DDoS attacks a greater challenge. Having a primitive yet effective implementation of human-readable hostnames is also nice.
All of these projects are available for people to use today.
Tor does have two upsides. The first is that it has a larger community. The second is that it has the Tor Browser, which I2P does not have an equivalent to, although the Tor Browser can be adapted to use I2P.
For example, take a look at I2P, which has been around almost as long as Tor. It has a lot in common with Tor, but has some key differences that may be appealing to some people. I2P nodes are capable of implementing something like an exit node (often called an "outproxy"), but there's no distinction between peers in I2P that designates one as an exit node. The project is more oriented towards hidden services, implementing its internal network, than it is in anonymizing connections to the clearweb. I think it's great that Tor exists, but I wish more people would consider I2P or at least simultaneously hosting their hidden services on both Tor and I2P. And if you really don't like running a Java runtime, Purple I2P exists and is written in C++.
There are also other networks like GNUnet, which slightly predates Tor, which is mostly file-sharing oriented, but with the goal of anonymity. It can do other things too but, from what I can tell, the project never gained much favor anywhere. Nevertheless, it still exists and is being worked on.
And I can't forget Freenet, or what's not referred to as "Hyphanet". I'll just call it Freenet for now because a lot of people still remember it. Freenet's focus is not only on anonymity but providing a distributed data store that is censorship resistant. This at least in part solves the issue of having to be online all the time in order to host a hidden service. It's been a long time since I've used Freenet, but supposedly the community is very good at discouraging crime and other unsavory elements. I haven't used the new iteration called Hyphanet.
All of these projects have significant differences from Tor, and some of these differences are seen by some as fixing significant flaws present in the Tor protocol that Tor can't reconcile. I2P's design of having no peer distinctions, in my opinion, is a vastly superior model for both security and plausible deniability. Its routing protocol also makes DDoS attacks a greater challenge. Having a primitive yet effective implementation of human-readable hostnames is also nice.
All of these projects are available for people to use today.
Tor does have two upsides. The first is that it has a larger community. The second is that it has the Tor Browser, which I2P does not have an equivalent to, although the Tor Browser can be adapted to use I2P.