TITLE: Topological space $\nRightarrow$ Metric space $\nRightarrow$ Normed space $\nRightarrow$ Inner product space (Examples)
QUESTION [9 upvotes]: If I have an inner product space, the hierarchy goes:
Inner product space $\Rightarrow$ normed space $\Rightarrow$ metric space $\Rightarrow$ topological space.
The reverse, however, is not always true. I'm currently struggling with this idea. So, it would help a lot if you could feature some examples like:

a topological vector space that is not a metric vector space
a topological (non-vector) space that is not a metric (non-vector) space
a metric vector space that is not a normed vector space
a metric (non-vector) space that is not a normed vector space
a normed vector space that is not a inner product space
a normed space that is not a vector space (if that does exist)

REPLY [4 votes]: a topological vector space that is not a metric space: take $V=C(\Bbb{R})$ where the topology is given by convergence on compact sets. A basis for this topology is given by sets of the form $$U_{K,f,\varepsilon} = \{ g : \sup_K |g-f| < \varepsilon \}$$ where $f \in V$ is continuous, $\varepsilon >0$ is a positive real number, $K \subset \Bbb{R}$ is a compact set.
a topological space that is not a metric space : take any infinite set with the cofinite topology.
I don't know the definition of "metric vector space" (if it exists).
a metric space that is not a normed vector space: take the ball $B(0,1)$ in any normed space
a normed vector space that is not a inner product space: take $L^{\infty}(\Bbb{R})$
a normed space that is not a vector space (if that does exist): it does not exist since by definition every normed space is a vector space with a norm.