What Christian companies, today, have no name by which they are known? In Revelation chapters one to three, there is a woman named Jezebel, whom Christ marks out as impenitent, Revelation 2:21; there is a sect, the Nicolaitans, whose deeds, Revelation 2:6, and doctrine, Revelation 2:15, Christ says he hates and he identifies them as being in both Ephesus and Pergamos; and there is a synagogue where falsely named 'Jews' meet whom Christ identifies in Philadelphia, Revelation 3:9, and he calls them liars.

But of the faithful, Christ mentions only one, in Pergamos - Antipas, who is deceased, a martyr, Revelation 2:13.

In these three chapters, He names no other individual and he names no other company by any communal name. He just states what town they are in.

If one wanted to go and meet them, one has no address (other than the town) and no description other than their characteristics - which he describes. 

My question is - are there any towns in the world, today, where a company of Christians meet together, yet have no identifying 'label' (other than the name of Christ, of course) ?
The only ‘label’ that matters is the ‘label’ of Christian.  A Christian is a person who belongs to Christ Jesus and who obeys Him.  Denominational labels are man-made and of no importance.  Jesus knows who belong to Him and His Church is not a denomination or a building but is a world-wide living entity made up of believers.  The short answer to your question is yes, there are lots of Christians around the world who meet regularly to worship God and study the Bible but who do not belong to any particular denomination.
A denomination is a church organization that exercises some sort of authority over the local churches that comprise it.  There are many Christians who meet together, in private homes or in rented halls, who do not have any identifying ‘label.’  Often, they are categorised as being non-denominational, which simply means they do not come under the authority of a specific denomination.   Non-denominational should never be confused with inter-denominational which is a church or an organization that incorporate different practices from various denominations.  The measure of any church, whether inside or out of a denomination, is not how it is organized nor what name it is called, but rather how faithfully it adheres to the teachings of the Word of God.
It is important to remember that the Body of Christ is interdenominational. We may choose labels for ourselves and others—and such labels have their place—but Jesus never assigned denominational tags. He said, “All those the Father gives me will come to me, and whoever comes to me I will never drive away” (John 6:37). The Body of Christ is made up of “everyone who calls upon the name of the Lord” (Acts 2:21), and the gospel of salvation by grace through faith unites all born-again believers who belong to Christ Jesus.
As for the events, persons and churches recorded in the first three chapters of Revelation, I found a useful article, part of which says this:

&quot;A normal hermeneutic or normal interpretation of Scripture means that unless the verse or passage clearly indicates the author was using figurative language, it should be understood in its normal sense. We are not to look for other meanings if the natural meaning of the sentence makes sense. Also, we are not to spiritualize Scripture by assigning meanings to words or phrases when it is clear the author, under the guidance of the Holy Spirit, meant it to be understood as it is written.
A simple outline for the book of Revelation is found in Revelation 1:19. In chapter one, the risen and exalted Christ is speaking to John. Christ tells John to “write, therefore, what you have seen, what is now and what will take place later.” The things John had already seen are recorded in chapter 1. The “things which are” (that were present in John's day) are recorded in chapters 2–3 (the letters to the churches). The “things that will take place” (future things) are recorded in chapters 4–22.&quot;  Source: https://www.gotquestions.org/Book-Revelation.html

Clearly, there is a warning to all Christians today against falling into sin and/or following false teachers.  Christians are identified by their words and deeds, by holding fast to the truth of God's Word and by showing Christ-like love to all persons.  By their fruits (the fruit of the Spirit) they will be known.