diff --git a/DESCRIPTION b/DESCRIPTION
index 115a187..d2834a2 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -13,6 +13,7 @@ Imports:
     uuid
 Suggests:
     knitr,
+    rcorpora,
     rmarkdown,
     testthat
 RoxygenNote: 5.0.1
diff --git a/R/ids.R b/R/ids.R
index 305fd86..3363a9c 100644
--- a/R/ids.R
+++ b/R/ids.R
@@ -20,8 +20,11 @@
 #'
 #' @export
 #' @author Rich FitzJohn
+#' @examples
+#' # For an example, please see the vignette
 ids <- function(n, ..., vals = list(...), style = "snake") {
   combine <- make_combine(style)
+  force(vals)
   gen <- function(n = 1) {
     combine(vapply(vals, sample, character(n), n, replace = TRUE))
   }
diff --git a/man/ids.Rd b/man/ids.Rd
index 4086f9a..fa542af 100644
--- a/man/ids.Rd
+++ b/man/ids.Rd
@@ -25,6 +25,9 @@ Either a character vector of length \code{n}, or a
 \description{
 Generic id generating function
 }
+\examples{
+# For an example, please see the vignette
+}
 \author{
 Rich FitzJohn
 }
diff --git a/vignettes/ids.Rmd b/vignettes/ids.Rmd
index 3a5f6ce..cfb4c9f 100644
--- a/vignettes/ids.Rmd
+++ b/vignettes/ids.Rmd
@@ -221,3 +221,99 @@ If you would rather past tense for the verbs, then pass `past=TRUE`:
 ``` {r }
 ids::sentence(4, past=TRUE)
 ```
+
+## Roll your own identifiers
+
+The `ids` functions can build identifiers in the style of
+`adjective_animal` or `sentence`.  It takes as input a list of
+strings.  This works particularly well with the `rcorpora` package
+which includes lists of strings.
+
+Here is a list of Pokemon names:
+``` {r }
+pokemon <- tolower(rcorpora::corpora("games/pokemon")$pokemon$name)
+length(pokemon)
+```
+
+...and here is a list of adjectives
+``` {r }
+adjectives <- tolower(rcorpora::corpora("words/adjs")$adjs)
+length(adjectives)
+```
+
+So we have a total pool size of `r length(adjectives) *
+length(pokemon)`, which is not huge, but it is at least topical.
+
+To generate one identifier:
+``` {r }
+ids::ids(1, adjectives, pokemon)
+```
+
+All the style-changing code is available:
+``` {r }
+ids::ids(10, adjectives, pokemon, style = "dot")
+```
+
+Better would be to wrap this so that the constants are not passed
+around the whole time:
+``` {r }
+adjective_pokemon <- function(n = 1, style = "snake") {
+  pokemon <- tolower(rcorpora::corpora("games/pokemon")$pokemon$name)
+  adjectives <- tolower(rcorpora::corpora("words/adjs")$adjs)
+  ids::ids(n, adjectives, pokemon, style = style)
+}
+
+adjective_pokemon(10, "kebab")
+```
+
+Here we'll use the word lists in rcorpora to generate
+identifiers in the form <mood>_<scientist>, like
+"warlike_charles_darwin".  These are similar to the names of
+docker containers.
+
+First the lists of names themselves:
+``` {r }
+moods <- tolower(rcorpora::corpora("humans/moods")$moods)
+scientists <- tolower(rcorpora::corpora("humans/scientists")$scientists)
+```
+
+Moods include:
+``` {r }
+sample(moods, 10)
+```
+
+The scientists names contain spaces which is not going to work for
+us because `ids` won't correctly translate all internal spaces to
+the requested style.
+``` {r }
+sample(scientists, 10)
+```
+
+To hack around this we'll just take the last name from the list and
+remove all hyphens:
+``` {r }
+scientists <- vapply(strsplit(sub("(-|jr\\.$)", "", scientists), " "),
+                     tail, character(1), 1)
+```
+
+Which gives strings that are just letters (though there are a few
+non-ASCII characters here that may cause problems because string
+handling is just a big pile of awful)
+``` {r }
+sample(scientists, 10)
+```
+
+With the word lists, create an idenfier:
+``` {r }
+ids::ids(1, moods, scientists)
+```
+
+Or pass `NULL` for `n` and create a function:
+``` {r }
+sci_id <- ids::ids(NULL, moods, scientists, style = "kebab")
+```
+
+which takes just the number of identifiers to generate as an argument
+``` {r }
+sci_id(10)
+```
diff --git a/vignettes/src/ids.R b/vignettes/src/ids.R
index 48755e4..d036600 100644
--- a/vignettes/src/ids.R
+++ b/vignettes/src/ids.R
@@ -163,3 +163,73 @@ ids::sentence(2, "dot")
 
 ## If you would rather past tense for the verbs, then pass `past=TRUE`:
 ids::sentence(4, past=TRUE)
+
+## ## Roll your own identifiers
+
+## The `ids` functions can build identifiers in the style of
+## `adjective_animal` or `sentence`.  It takes as input a list of
+## strings.  This works particularly well with the `rcorpora` package
+## which includes lists of strings.
+
+## Here is a list of Pokemon names:
+pokemon <- tolower(rcorpora::corpora("games/pokemon")$pokemon$name)
+length(pokemon)
+
+## ...and here is a list of adjectives
+adjectives <- tolower(rcorpora::corpora("words/adjs")$adjs)
+length(adjectives)
+
+## So we have a total pool size of `r length(adjectives) *
+## length(pokemon)`, which is not huge, but it is at least topical.
+
+## To generate one identifier:
+ids::ids(1, adjectives, pokemon)
+
+## All the style-changing code is available:
+ids::ids(10, adjectives, pokemon, style = "dot")
+
+## Better would be to wrap this so that the constants are not passed
+## around the whole time:
+adjective_pokemon <- function(n = 1, style = "snake") {
+  pokemon <- tolower(rcorpora::corpora("games/pokemon")$pokemon$name)
+  adjectives <- tolower(rcorpora::corpora("words/adjs")$adjs)
+  ids::ids(n, adjectives, pokemon, style = style)
+}
+
+adjective_pokemon(10, "kebab")
+
+## Here we'll use the word lists in rcorpora to generate
+## identifiers in the form <mood>_<scientist>, like
+## "warlike_charles_darwin".  These are similar to the names of
+## docker containers.
+
+## First the lists of names themselves:
+moods <- tolower(rcorpora::corpora("humans/moods")$moods)
+scientists <- tolower(rcorpora::corpora("humans/scientists")$scientists)
+
+## Moods include:
+sample(moods, 10)
+
+## The scientists names contain spaces which is not going to work for
+## us because `ids` won't correctly translate all internal spaces to
+## the requested style.
+sample(scientists, 10)
+
+## To hack around this we'll just take the last name from the list and
+## remove all hyphens:
+scientists <- vapply(strsplit(sub("(-|jr\\.$)", "", scientists), " "),
+                     tail, character(1), 1)
+
+## Which gives strings that are just letters (though there are a few
+## non-ASCII characters here that may cause problems because string
+## handling is just a big pile of awful)
+sample(scientists, 10)
+
+## With the word lists, create an idenfier:
+ids::ids(1, moods, scientists)
+
+## Or pass `NULL` for `n` and create a function:
+sci_id <- ids::ids(NULL, moods, scientists, style = "kebab")
+
+## which takes just the number of identifiers to generate as an argument
+sci_id(10)